Reflections – 2016

January 1, 2017 by grahamrob in Autoguiding, Comments, Deep Sky Objects, General Astronomy, History, Imaging, Widefield Imaging and tagged Andromeda, Arizona, Einstein, Galaxies, Messier Objects, Milky Way, Orion, Photography, Science, Utah | Leave a comment

2016 was the second full year of Watch This Space Man (WTSM) and once again it’s been something of a mixed period. Faced with a major, apparently insoluble problem, by mid-year I actually thought of giving up but by year-end it’s all come good again, in fact very good. Reflections is a look back at the ups-and-downs of the past year, astronomically speaking and a peek into the next twelve months, which one way or another could determine the future of my astrophotography.

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I have been astonished by the interest in this website, with some 7,000 visits and 14,000 page views from more than 65 different countries during the year, the list is quite amazing. Though I write this blog for myself, I am increasingly aware of this unsolicited readership – you are all most welcome and I would be very pleased to hear from anyone who would like to get in touch with queries, comments or just to say hello – contact details are in the Contact drop-down section of the About main menu.

reflections-2016

JANUARY TO MARCH

The year started poorly, got much worse, then finally improved. Using my recently acquired Vixen Polarie I was pleased to start the year with an image of Barnard’s Loop, something notoriously difficult to photograph and had previously eluded me. Sadly I was not so successful with the Milky Way and have reluctantly come to the obvious conclusion that this can only be imaged in much darker skies than I’m ever likely to experience located just to the south of London and close to Gatwick airport!

As Orion starts to move on after Christmas and especially from February, I struggle to find suitable imaging targets; Coma Berenices and other constellations at this time contain numerous galaxies but they’re mostly too small for my William Optics GT81 and otherwise what might be doable I have already done before. Notwithstanding, after looking carefully I came across two HII nebulae still lurking in the early evening. The size and Ha-light of NGC 2174 Monkey Head Nebula and IC 2177 Seagull Nebula, provided just what I was looking for. Located close to Gemini and Monoceros constellations, both these DSOs are within the part of the Milky Way section of the sky, an area that thankfully produces many other similar opportunities at this time of the year for a modded DSLR camera.

Monkey Head Nebula

It’s often the small things that either alone or cumulatively can help transform the outcome with astrophotography. The quarterly period finished by acquiring two new pieces of equipment, one which could help improve the set-up and operation of the mount, the other which I hoped would help me move to the next level of imaging.

When working in the dark and worse still in the cold, the ergonomics and general convenience of operating the equipment becomes paramount. Since starting to use EQMOD-ASCOM and Cartes du Ciel for mount control and tracking, I encountered the problem of having to be in two places at the same time; in this case co-ordinating adjustments at the mount and the computer, in particular when making and syncing star alignments. The answer to this conundrum was a gamepad, which I purchased for a nominal sum on eBay and after watching the inimitable Chris Shillito’s video on setting up and using a gamepad with EQMOD-ASCOM, have never looked back. By using the gamepad the telescope can now be manually slewed, centred and synced on any object whilst remaining at the scope, thereby making the process of alignment much quicker and convenient.

Wireless gamepad provides extensive control of critical alignment functions without being at the computer: front x4 buttons are assinged to set various slew rates, the mount-telescope can be directed either via the rear (right) joystick or POV buttons on the right, button-1 parks and button-2 syncs. Other buttons have yet to be allocated.

Starlight Express Lodestar x2 Guide Camera can be used either via the mount’s ST4 port or via ASCOM and the computer for pulse guiding.

At the end of 2015 it was my intention to start guiding in the coming year, a prerequisite for the long exposures necessary to increase data capture and thus hopefully improve image quality. I had originally intended to use my ZWO ASI120 MC camera together with a William Optics 50mm guidescope for this purpose but there always seemed to be other problems to overcome first and to be honest, I was somewhat intimidated about tackling the black art of guiding. I was finally prompted to do something about this when in March a second-hand Starlight Express Lodestar X2 autoguide camera came up on the UK Astronomy Buy & Sell. From previous research I knew this was considered to be a very good and popular guiding camera, so as it had only just been posted on the website, I immediately went for it and was successful – timing is everything. Inevitably I had problems setting-up and in particular getting the camera to focus – which was my own fault – but by the end of March I was guiding! Truth is my guiding at this stage was not very good and I needed to look further into using the PHD2 guiding software but nonetheless, the equipment was at least now working together!

No	Date	Object*	Name
1	07/01/16	Orion	Barnard’s Loop
2	14/01/16	Orion	Barnard’s Loop
3	02/02/16	Catalina	Comet
4	02/02/16	Milky Way
5	10/02/16	IC 2087	Dark nebula
6		NGC 2174	Monkey Head Nebula
7		IC 2177	Seagull Nebula

*Record of quarterly photographic images taken in 2016

APRIL TO JUNE

After finishing the previous quarter on something of a high note by getting PHD2 working for the first time, I was now hopeful that from herein my exposures and thus images would show improvement – unfortunately I was soon to be very disappointed.

In April we went on a trip to the Southwestern USA – something of a geological pilgrimage for my wife and I (we are both geologists) – to see the Grand Canyon, Monument Valley, Bryce Canyon and Zion National Park as well as many other similar areas. Prior to going I had purchased a Sigma 10mm-20mm wide-angle lens in anticipation of all the big views that are characteristic of the region and was not disappointed by the lens or the scenery.

Being largely an uninhabited wilderness area, I also took the Vixen Polarie with a plan to at last capture images of the Milky Way. Unfortunately, whilst I had checked the sky beforehand on Cartes du Ciel, I think I must have made an error with the dates. We did get clear skies but unfortunately it turned out to be a full moon whilst there, which ruled out any hope of seeing, let alone imaging the Milky Way; oh well there’s always another day and it’s not going anywhere in the meantime. Notwithstanding I did manage some pleasing nightscapes at Monument Valley and Bryce Canyon.

IMG_6235 (Large)

Given my initial guiding success prior to visiting the USA, I had been looking forwards to getting to grips with improving guiding and imaging on my return. Furthermore, on 6^th May there was a rare solar transit of Mercury and in preparation, the week before I set up and tested all the equipment and then successfully took some test images of the Sun using a Baader solar filter. All was well on the appointed day which was also fortunately clear and sunny, so that shortly before contact I was all set and ready to try and capture the movement of a small black dot (Mercury) across the face of the Sun. Unfortunately it was not to be and the weeks that followed almost marked the end of my still nascent hobby of astrophotography!

In short, EQMOD crashed when I turned on the DSLR camera to image the transit! I tried re-booting and checked every other piece of equipment numerous times but to no avail. I subsequently spent weeks trying to track down the problem, checking and re-checking every cable, piece of equipment and updating or reinstalling all the relevant software without success. The nature of the problem strongly suggested there was a conflict between EQMOD-ASCOM and the camera and I therefore turned to the EQMOD forum for help, without success. Somewhat late in the day and by now desperate, I posted the issue on SGL and quickly received a reply from someone who had had a very similar problem, which though also very difficult to identify, turned out to be a very small break in the outer cover of the DSLR AC/DC power adapter cable. It’s not clear to me why this matters but I bought a new adapter and as they say, Bob’s your uncle, it worked! I have looked very carefully at my adapter and cable and can see nothing wrong but am very thankful for the advice.

AC/DC Adapter: How can something as basic as this cause so much disruption?

It seems ridiculous that this very minor problem was nearly terminal but just in case it happens again I have since bought another spare power adapter. Together with my daughter’s wedding in early June and the adapter meltdown, imaging for two of the three months during this period was almost non-existent. Still by July I was ready to start again but by then there was no astronomical darkness!

No	Date	Object	Name
8	April	USA	Monument Valley etc
9	06/06/16	M5	Globular cluster
10		M13	Globular cluster
11		M57	Ring Nebula

JULY TO SEPTEMBER

After the carnage of the last quarter, I was then unable to resume imaging in July due to travel commitments. So I used what time was available to improve my knowledge of PHD2 and once again, check everything was now working ready for the return of astronomical darkness and better night skies from 20^th July; I am of course now paranoid of another similar breakdown. At the start of August I manged to obtain a just passable image of the Eagle Nebula for the first time. Then shortly afterwards on the evening of 11^th / 12^th August, clear skies produced a decent night for viewing and imaging a few of this year’s Perseids meteor shower. But it was at month-end and continuing into September that my imaging in 2016 finally took off.

m27-comps-paintfile

At that time the weather was consistently dry and warm, providing more than a week of clear skies and almost nightly imaging. Dark nebulae are interesting features I’d hitherto not recognised as imaging opportunities and was therefore intrigued to successfully image the E-Nebula at this time. Thereafter I used the opportunity of the weather window to experiment with PHD2 by using M27 the Dumbbell or Apple Core Nebula as a control imaging object. Of course, each year is different but I’ll try to use any similar conditions in the future to sort out and develop old and new techniques, such unusual moments are precious for UK astronomers. At the end of nearly two tiring weeks I had PHD2 working quite well and have not looked back since. As a result of this work soon thereafter obtained good images of the Andromeda Galaxy, as well as the Veil, Crescent and Ring Nebulae.

No	Date	Object	Name
12	07/08/16	M16	Eagle Nebula
13		M11	Globular
14		B142-3	Dark E-Nebula
15	11/08/16	Perseids
16	23/08/16	LDN 673	Dark Nebula
17		NGC 6781	Planetary Nebula
18		M27	Dumbbell Nebula
19		Albireo	Double star
20		Moon
21	28/08/16	M11	Globular cluster
22		NGC 6905	Blue Flash Neb
23		Albireo	Double star
24		15 Aquilea	Double star
25		NGC 6960	W Veil / Witch’s Broom
26		M32	Andromeda Galaxy
27	29/08/16	M27	Dumbbell Neb
28		NGC 6960	W Veil / Witch’s Broom
29		NGC 7814	Pegasus galaxy
30		M15	Globular
31		M27	Dumbbell Nebula
32		M27	Dumbbell Nebula
33	08/0916	M27	Dumbbell Nebula
34		M27	Dumbbell Nebula
35		NGC 6960	W Veil / Witch’s Broom
36		NGC 6960	W Veil / Witch’s Broom
37		M31	Andromeda Galaxy
38	11/09/16	NGC 6888	Crescent Nebula
39		NGC 6992	Eastern Veil (NGC 6995)
40	13/09/16	M57	Ring Nebula

OCTOBER TO DECEMBER

Normal conditions resumed later in September and into the final quarter in the form of overcast skies. A minor break in the weather allowed a crack at the M33 Triangulum Galaxy towards the end of October but only in late November did another clear period occur, by which time the winter sky had arrived and temperatures had fallen to nearly 0^oC.

M33 Triangulum Galaxy – consisting of some 40-billion stars, the photons in this image have travelled 3-million light years in order to reach my camera sensor! | WO GT81 + modded Canon EOS 550D & FF guided | 18 x 300 secs @ ISO 800 & full calibration | 22nd October 2016

Unfortunately I am unable to establish a permanent observatory here at Fairvale and have to take-out the bring-in all the astronomy equipment each time. Apart from being inconvenient this has two practical disadvantages: (i) it can be uncomfortable even unpleasant working outside in such temperatures, and (ii) it is necessary to polar and star align every time; on occasion when using SynScan and EQMOD-ASCOM it can take up to 2-hours before starting imaging. Fortunately, I think I have now sorted out both these problems which should greatly help in the future.

By re-configuring the computer, mount and camera wiring, combined with establishing a wireless link between my tablet and the computer, once set-up I can now control most of the functions from indoors. The comfort of being indoors benefits operating in general and especially thinking, which can be quite difficult when astroimaging and made even harder when it is cold.

With prolonged periods of clear weather in the second-half of the year, I was sometimes able to set-up and leave the equipment for a few days under a waterproof cover, which meant that from day-to-day I could be up-and-running each time in less than 30 minutes! However, I expect this will only rarely be possible and nightly set-ups are likely to continue to be the norm. Fortunately, I have also recently discovered two techniques that should help both streamline and improve star and polar alignment in the future.

In addition to guiding, PHD2 has a very good polar alignment facility that eliminates the use of the SynScan handset and enables the procedure to be carried out from the computer; it can also be undertaken without sight of the Polaris star, which is a major problem at Fairvale Observatory where it is totally obscured by my house. At times when the mount can be left outside, I can also save and subsequently re-use the star-alignment model in EQMOD-ASCOM. All-in-all these and other procedures have made a very positive impact on my astronomy and astroimaging. The outcome of these changes led to a decent sequence of imaging with which to finish the year and, furthermore, hopefully provides a strong foundation for continuing improvements in 2017.

No	Date	Object	Name
41	22/10/16	M15	Globula cluster
42		M33	Triangulum Spiral Galaxy
43	28/11/16	M45	Pleiades
44		NGC 2024	Horsehead Nebula
45		M42	Orion Nebula
46	29/11/16	Hyades	Open star cluster
47		NGC 2244	Rosette Nebula
48	30/11/16	NGC 1499	California Nebula
49		IC 405	Flaming Star Nebula
50	03/12/16	M74	Spiral Galaxy
51		M77	Spiral Galaxy
52		M1	Crab Nebula
53		IC 2118	Witch’s Head
54		M78	Reflection Nebula
55	04/12/16	SH2-264	Lamda Orionis
56		SH2-261	Lower’s Nebula

ETCETERA

A few other astronomy and imaging related matters helped shape the past year for me. After coming across WTSM, I was surprised to be contacted by the Purley Photography Camera Club to give a lecture on astrophotography in March. I’m pleased to say the event went very well and, furthermore, the process of compiling the presentation beforehand helped expand my own knowledge of the subject too.

TTT Cover

In May I received a sun dial installed on a carved Purbeck Stone plinth as a retirement present. As a time piece it’s accuracy is limited but it is a beautiful addition to my garden and solar astronomy for which I am very grateful. By coincidence, later in the year I also came across a simple but charming sun dial set into the ground by the upper lake at Earlswood Common, a short walk from my home and Fairvale Observatory. Intriguingly it works by standing on a central stone, located depending on the season, and then uses your own shadow to read off the time – clever.

Sun dial at Earlswood Common

My new sun dial

In September we visited Lacock Abbey in Wiltshire, home of William Fox Talbot in the 19th Century – photography pioneer and notable for developing photographic fixing and printing. The photography museum there is very good and it was fascinating to see his place of work in the house, where the very first photographic print is also displayed. His contribution to photography is unique and today he is generally recognised as the father of modern photography.

william-henry-fox-talbot-with-camera-141697035181903901-141210123557

As a Londoner born and bread, I like to think I know the city well and over my lifetime have visited most of its unique sites, old and new. However, for some inexplicable reason I had never been to Westminster Abbey, so decided to put that right in November. It is, of course, a building of unparalleled history, with numerous graves and memorials of centuries of kings & queens, as well as scientists, explorers, poets, actors etc. Noteworthy amongst these for the astronomer is the physicist and mathematician Sir Isaac Newton and Second Astronomer Royal, Edmond Halley.

I must next give mention to the man who throughout the year dominated my reading, learning and thinking – Albert Einstein. His work during the early part 20th Century still dominates today’s physics and astronomy. We continue to make ground breaking discoveries that substantiate and build on his ideas that were originally postulated over 100-years ago. Pictures only recently obtained using the the Hubble telescope have spectacularly demonstrated the effect of gravitation lensing and in 2016 for the first time ever the existence of gravitational waves was confirmed. This year I therefore decided to understand the man and his work better. During the first half of the 2016 I read Walter Isaacson’s excellent biography of Einstein and have recently completed and 8-week Stanford University course on the Special Theory of Relativity. They were both very enjoyable, immensely interesting and time well spent.

CMB some 380,000 after Big Bang.

Einstein vindicated: gravitational lensing

Finally, this Christmas I was surprised and very pleased to receive a printed, bound copy of the WTSM blog for the period since its inception on 5th August 2014 until 10th November 2016. A lot of work has gone into producing this blog and I’ve always been concerned that somehow something might go wrong with the website or internet and it would all be lost. This book now safely preserves in print all the blogs and images posted during the aforementioned period. The production is generally very good and I have already enjoyed re-reading some of my blogs once again.

WTSM: The Book!

Favourite Images

As a result of the aforementioned issues, 2016 has certainly been a year of two halves. Having resolved the equipment problem and started to employ some very useful new techniques and software, I was eventually able to obtain some good images. My personal favourites in no particular order are shown here below:

Barnard’s Loop & Lamda Orionis Nebula : Vixen Polarie & modded Canon 550D + Sigma UWA @ 20mm | 11 x 240 secs @ ISO 1,600 + darks | 7th January 2016

Monument Valley by Night: order of buttes same as daytime photo above. Canon 700D + 10mm Sigma wide-angle lens | 20 x 15 secs @ ISO 6,400 | 10th April 2016

B142/3 Barnard Dark E-Nebula

M27 Apple Core Nebula | William Optics GT81 + 50mm Guide Scope & 10-point EQMOD-ASCOM alignment model | modded Canon 550D + Field Flattener | 3 x 300 secs @ ISO 1,600 & full calibration, 90% cropped | 30th August 2016

M31 | WO GT81 + modded Canon 550D & FF | 10 x 300 secs @ ISAO 1,600, darks + flats | 8th September 2016

First ever print, taken at Lacock Abbey 1835

The same picture by me September 2016

Round-up & goals for 2017

Despite the frankly awful start to the year, astronomically speaking 2016 finished on something of a high. Furthermore, contrary to initial indications I was in the end partially successful in achieving some of my objectives set out at the beginning of last year:

RECORD CARD – 2016
Goal	Specifics / Results	Outcome
*Increase imaging exposure times*	Improved equipment set-up and alignment and successfully started autoguiding with exposure times of up to 8-minutes.	DONE
*Improve processing*	Started using newer version of Photoshop CS2 + other related software. Improvement with post-processing using online tutorials and Nik Syzmanek’s booklet Shooting Stars.	GETTING THERE
*Start widefield imaging*	Purchased Vixen Polarie, with portability put to use in the USA but did not make UK dark sky sites as planned.	GETTING THERE

Getting better: PHD2 working screen 30th November 2016, DEC is good but room for improvement with the RA settings. Notwithstanding, the impact of tracking and image quality is noticeable.

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I’m concerned about setting more goals or the forthcoming year but I think it helps, so here goes:

Improve processing: As the headmaster’s report would say “room for improvement” and I will try. I have purchased Warren Keller’s book Inside PixInsight, considered by many to be the gold standard of post-processing software but is a nightmare to learn – this may be a step too far for now, we’ll have to see – maybe 2018?

Expand and improve widefield imaging: First – use the Vixen Polarie as had been intended last year to obtain nightscape images at UK dark-site locations. Second – look at ways of using a widefield set-up with the mount more successfully.

Start LRGB imaging: I spent a lot of time in 2016 considering the question – what next? I am keen to image smaller DSO objects, in particular galaxies and was on the verge of purchasing a larger telescope – probably another refractor. However, after attending a talk by Nik Syzmanek, one of Britain’s foremost astrophotographers, I have come to the conclusion that the next step should probably be a move to LRGB imaging, which if successful probably has the greatest potential to improve my pictures – let’s hope so.

Looking back 2016 was a funny old year, which for me was defined by three experiences:

Despite two wonderful periods at the end of August and November the weather for astronomy was mostly awful, with cloud cover for weeks on-end and when it was clear, it was a full moon – frustrating or what?

I had already learned that patience and perseverance are required in large quantities for astroimaging but the equipment break-down in May and June was so severe and apparently insoluble that, together with the aforementioned cloudy skies, I really thought of giving up.

However, this time there is a happy ending: after I finally solved the equipment problem and started autoguiding, I feel I have eventually made some great strides with my imaging in 2016 which, furthermore, holds much promise for the coming year and I hope can record in WTSM’s Reflections at the end of 2017.

Watch this space!

Photons & Photography

December 20, 2016 by grahamrob in Deep Sky Objects, Equipment, General Astronomy, History, Imaging, Processing, Universe and tagged Einstein, Messier Objects, Photography, Science | 1 Comment

william-henry-fox-talbot-with-camera-141697035181903901-141210123557

I’ve been interested in photography from a young age. As I child I played with my parent’s Kodak box camera and, as far as I can remember, my first camera was a Kodak Brownie at the age of about nine. It’s a wonderful medium that I have now experienced for over 50-years, on land, underwater and now for astrophotography.

My cameras

I’d like to think I know a thing or two about photography by now; underwater photography and digital astrophotography have been particularly challenging in different ways but the latter is a real eye opener that has expanded my knowledge of digital imaging significantly. Capturing images of distant objects that can only be seen with the use of sophisticated equipment and complex processing also requires an in-depth understanding of light itself.

Basic working concept of digital sensors

Modern camera sensor

Having spent the first half of this year reading Einstein’s biography, I have recently started an online course at Stanford University on his ground-breaking Special Theory of Relativity. Einstein’s many insights into the physical world are profound, which more than 100-years on still challenge most of us to understand. Light was at the core of his famous 1905 paper, in particular it’s duality as a waveform and light quanta, or photons – defined as a quantum of electromagnetic radiation. His concept of the photoelectric effect has enabled the development of today’s digital camera sensors and CCDs. The core principal is the production of electrons as light shines onto a material, whereby the light (photon) knocks out an electron which can then be collected electronically – the basis of digital photography.

Camera obscura at Lacock

Camera obscura image

Lacock Abbey

In September I visited Lacock Abbey in Wiltshire, initially a 13^th century nunnery which is now run by the National Trust. Today it is better known as the home of William Henry Fox Talbot (1800 – 1877) – mathematician, astronomer and archaeologist but most famously the inventor and pioneer of photography, notably developing, fixing and printing. The window photograph below (left) was taken at Lacock Abbey in August 1835 and is recognised as being from the oldest ever camera negative produced by Fox Talbot, on the right is the same window in 2016.

First ever print, taken at Lacock Abbey 1835

The same picture by me September 2016

In the early 19^th century Thomas Wedgwood had made photograms – silhouettes of leaves and other objects – but these faded quickly. In 1827, Joseph Nicéphore de Niepce produced pictures on bitumen, and in January 1839, Louis Daguerre displayed his ‘Daguerreotypes’ – pictures on silver plates – to the French Academy of Sciences. Three weeks later, Fox Talbot reported his ‘art of photogenic drawing’ to the Royal Society, which subsequently became the de facto basis of modern film photography.

Fox Talbot’s desk in his study at Lacock Abbey

Fox Talbot lived and worked at the Abbey for most of his life. As well as an excellent museum, which details the history of photography and photographic processes, the house contains his rooms where he developed (no pun intended) the aforementioned inventions and is surely a ‘must do’ visit for any keen photographer. Like many at that time he was a polymath, with notable friends and accomplices who worked in similar and other scientific fields:

Sir John Herschel – astronomer, mathematician, botanist & chemist, Gold Medal winner and founder of the Royal Astronomical Society, son of William Herschel who discovered Uranus.

Charles Babbage – mathematician, philosopher, mechanical engineer, considered “the father of the computer”;

William Whewell – leading 19^th century scientist, recognised in the fields of architecture, mechanics, mineralogy, moral philosophy, astronomy, political economy, and the philosophy of science;

Sir Charles Wheatstone – physicist, inventor of stereoscopic photography, the telegraph & accordion;

Sir David Brewster – physicist specialising in optics, mathematician, astronomer & inventor of optical mineralogy and the kaleidoscope;

Peter Roget – physician, theologian, lexicographer and publisher of Roget’s Thesarus.

This particular group are now remembered by a table setting in the Abbey’s dining room, where they gathered for dinner; the mind boggles at the conversation!

Fox Talbot’s pioneering photography work preceded the early 20^th century understanding of light that arose from Einstein and its more recent application in semi-conductors as camera sensors, of which I am sure he would have approved. At that time the Universe outside of our galaxy was also unknown and he would have marvelled further at the thought of imaging other such distant galaxies such as M33 below; like photons, photography has come a long way since his death in 1877.

M33 Triangulum Galaxy – consisting of some 40-billion stars, the photons in this image have travelled 3-million light years to reach my camera’s sensor! | WO GT81 + modded Canon EOS 550D & FF guided | 18 x 300 secs @ ISO 800 & full calibration | 22nd October 2016

The future is not what it used to be

October 7, 2016 by grahamrob in Autoguiding, Deep Sky Objects, General Astronomy, Imaging, Processing, Software and tagged Andromeda, Photography, Veil Nebula | 3 Comments

sftf

If I’m honest my astrophotography has so far often been – never mind the quality feel the width! That is to say, I have tended to chase objects – nebulae, galaxies, planets, solar – in order to learn about my equipment and the night sky as well as just have fun recording images of these distant worlds. Nothing wrong with that is there? It’s not that I don’t aspire to obtaining the best image possible and I have made good progress since starting out but I’ve often felt constrained by circumstances.

Although I’ve generally been happy with my images, it’s a fact that there are a number of factors that altogether make astrophotography difficult, especially here at Fairvale Observatory:

Poor weather & persistent cloud cover
The Moon
Buildings & trees obscure sightlines
Light pollution from Gatwick airport
Numerous aircraft passing overhead
Equipment problems
Software problems
Equipment and software failures
Equipment limitations
Need to assemble equipment each time

Bad weather, frequent cloud cover, limited sightlines, aircraft trails and the inevitable monthly occurrence of the Moon limit imaging opportunities here.

Under these circumstances I usually need to grab what I can, frankly it’s a miracle I’m able to achieve anything sometimes; Met office statistics for the six-months period from September 2105 showed cloud cover was a record 68% compared with an historical average of 32% for that time of year, as a result it was unusual to be able to undertake astrophotography more than once month, if that! Wherever possible I therefore have to target those items that I can improve easily, quickly and cheaply dealt with, which is mostly equipment. Buoyed by renewed enthusiasm from my recent autoguiding success, I now intend to concentrate on changing some key items that I hope will eventually bring about more noticeable improvements.

sign2 For a while I have been thinking about getting a larger telescope, in order to get to those faint fuzzies that are beyond the capabilities of the otherwise excellent William Optics GT81. As usual the choice is a minefield of possibilities, each with inevitable imaging pros and cons! I started thinking about a Ritchey Chrétien or Schmidt Cassegrain but I have really appreciated the qualities of the aforementioned WO GT81 and am now erring towards a larger refractor. However, after further consideration I am now considering a change of priorities.

In September I was fortunate to attend a presentation on image processing by Nik Szymanek who, it has to be said, really knows his onions when it comes to astrophotography; I was intrigued and impressed to find out he also hails from my neck of the woods when I was a teenager in Essex and is an accomplished rock drummer – something I also used to meddle with in the past – what a geezer, as he would say. The talk was very instructive and I am now ploughing my way through Nik’s fabulous book on the subject called Shooting Stars (published in magazine form by Astronomy Now). Such personal, first-hand and relevant guidance is difficult to find in astroimaging and the book has a wealth of really practical information and useful advice that I wished I’d known sooner. Good equipment is important but in the world of digital imaging the significance of processing cannot be overstated. It’s a dark art alright (no pun intended) but Nik’s work has strengthened my resolve to improve my processing knowledge and I’m even more determined to raise the bar during the forthcoming winter.

20160708-shooting-stars-for-store Following Nik’s talk and listening to others, the penny that has now dropped is that for the moment it’s not the telescope but the camera that needs changing. After careful thought it’s apparent that I already have very good set-up, yes a bigger aperture would be good for those smaller fuzzies but the 81mm apochromatic refractor I already own is an outstanding telescope that still has much potential when combined with the AZ-EQ6 mount and now autoguiding.

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The addition of a modded DSLR at the beginning of last year had a significant impact on my images, especially with Ha dominant DSOs which I literally saw in a new light using this camera. I have continued with the DSLR for a number of reasons but mainly because I am familiar with such cameras which are relatively easy to use and produce reasonable results when starting out with astrophotography. However, listening to Nik and reading the forums and elsewhere, I have come to accept that the best way forwards should now be a CCD-type camera. As a result I am deep in my research of CCD issues and possible cameras – this could take some time and won’t be cheap!

The operation of CCDs is quite different to a DSLR and I’m sure will involve a whole new period of pain but it’s clear that this is the best route for now if I am to significantly improve my astrophotography. Other than the technical challenges CCD imaging presents, I am however concerned about the greater number of frames needed for LRGB + calibration and how that’s going to work with the weather restrictions and other problems I have but it’s got to be worth a try.

However, before setting out on this daunting task I first slewed the camera towards a few familiar objects just to experiment with guiding and assess the benefits it might bring to my imaging in the interim. A spell of unusually good weather in late August – early September was too good to miss and with guiding I was able to achieve exposures of up to 8 minutes. However, for the moment I continued to limit the number of Subs and calibration frames just to ensure I could shoot more objects in the available time, plus you never know when the next bank of cloud will roll in – old habits die hard!

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Looking at the results below demonstrates my progress when compared with earlier images but the limited number of frames and calibration has probably restricted the full benefit of what might be gained from guiding and some shots remains quite noisy. Nonetheless, I now have high hopes that the potential is within my grasp to make real progress in achieving better image quality. I am not convinced I have yet reached a turning point but I am well positioned to navigate the tasks required to get there, which are now more clearly understood and in my sights or should that be RDF – watch this space!

M31 Andromeda Galaxy

WO GT81 + unmodded Canon 700D & FF| 10 x 30 secs & ISO 800 | August 2014

WO GT 81 + modded Canon 550D + FF | 9 x 120 secs @ ISO 1,600 | 19th September 2015

WO GT81 + modded Canon 550D & FF & PHD guiding | 10 x 300 secs @ ISO 1,600 calibration | 8th September 2016

NGC 6905 Western Veil Nebula – The Witch’s Broom

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Canon 700D | 20×90 sec + darks.bias/ flats @ ISO 800

WO GT81 + modded Canon 550D + FF & PHD guiding | 5 x 300 secs @ ISO 1,600 & calibration | 8th September 2016

NGC 6888 Crescent Nebula

WO GT81 + modded Canon 550D + FF | 19th October 2015

WO GT81 modded Canon 550D + FF & guiding | 10 x 300 secs @ ISO 1,600 & calibration | 11th September 2016

NGC 6992 Eastern Veil & Bat Nebula

Eastern Veil Nebula – NGC 6992 (right) & NGC 6995 (left). WO GT81 + Canon 700D & FF | 29 x 120 secs + darks/bias?flats @ ISO 1,600

Eastern Veil Nebula (NGC 6922 & 6995): WO GT81 & modded Canon 550D + FF & guiding | 10 x 300 sec @ ISO 1,600 + darks | 11th September 2016

Forbidden Fruit

September 21, 2016 by grahamrob in Autoguiding, Deep Sky Objects, General Astronomy, Imaging, Software and tagged DSO Imaging, Guiding, Messier Objects, Nebulae, Photography | 3 Comments

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Soon after embarking on my astrophotography adventure just over two years ago it became apparent that after getting the basics right – polar & star alignment, focus, image capture etc. – the Holy Grail of imaging is increased exposures times, thereby collecting more of those elusive photons that have travelled across the Universe. The first step to achieving this goal is tracking, which since purchasing my AZ-EQ6 mount in 2015 I have been successfully improving over time, on a good day achieving 180-second exposures and from time-to-time resulting in some decent images. However, the light from DSOs is often very feint and can require much longer times, which is easier said than done.

At the same time as acquiring the aforesaid mount and a William Optics GT81 telescope I also purchased a William Optics 50mm guide scope, with which I intended to start guiding and thus push exposures above my 3-minute barrier. Despite these aspirations, through a combination of events and my unease about the apparent difficulty of guiding, the guide scope has remained unused – until now. Having recently purchased a dedicated Starlight Express Lodestar X2 guide camera, I have finally been emboldened enough to give it a try.

Starlight Express Lodestar x2 Guide Camera can be used either via the mount’s ST4 port or via ASCOM and the computer for pulse guiding.

I initially struggled to set up the guide scope and get the guide camera working together. In particular obtaining focus proved very difficult; like the GT81 the guide scope focus turns out to be achieved within a very short distance that is measured in fractions of millimetres, which in this case required the insertion of an extension tube.

Reminiscent of the Space Shuttle on its Boeing 747 transport plane! The William Optics 50mm guide scope + Lodestar X2 guide camera neatly mounted atop the GT81 imaging scope using the integral rings.

Thereafter the big challenge, which I had previously avoided, was to start using the very popular PDH guiding software; Push Here Dummy (PHD) is named tongue-in-cheek by its original creator Craig Stark and is an amazing but somewhat intimidating piece of software.

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The principle is simple – find a star within the FOV and use it as a fixed reference point from which to assess and then correct small tracking errors in order to achieve better tracking, which thereby maintains pinpoint accuracy and enables longer exposure times, thus avoiding trailing of the sky and the objects being imaged. Its use is regarded as something of a dark art but I have finally grasped the nettle with some success. After months of clouded skies followed by an almost fatal equipment failure (see here for more), a period of exceptionally good weather and clear skies since late August provided the ideal opportunity to get to grips with this challenge that has so far eluded me.

At first I used a couple of sessions to overcome some past problems and ensure that everything was stable and worked well for basic tracking and imaging, in particular:

Repair and improve the imaging camera’s AC/DC adapter lead;

Where possible improve all other leads and connections – once bitten …..! In this respect I have significantly re-arranged and tidied up the many power, control and camera leads, which has included the addition of right-angle USB / mini-USB camera connectors that now makes plugging-in easier and produces less strain on the connections i.e. more secure. Simple, cheap and something I should have undertaken long ago;

Revisit EQMOD-ASCOM in order to achieve more robust tracking – especially reviewing the star alignment procedures;

Fit the guide scope using the rings incorporated onto the GT81 OTA, subsequently re-balancing the equipment and improve the mount’s feet positioning.

At this point I spent a couple of nights just playing with the equipment and in particular EQMOD-ASCOM, so as to obtain the best possible alignment; having suffered an enforced absence from imaging I just wanted to have some fun again too. At the end of this process, first using SynScan for polar alignment before switching to EQMOD-ASCOM + Cartes du Ciel for star alignment, I successfully produced a good 10-star alignment model which was then saved for future use. The resulting images already showed some improvement but I still had to tackle PHD. With unusually good weather I decided to leave the final set-up outside under cover, thus preserving the settings for a shot at the aforementioned task of guiding next time. In the interim I then needed to read the operating instructions and watch numerous videos on the use of PHD.

EQMOD-ASCOM 10-point alignment model. With an obstructed view of the northern sky by my house, all points are inevitably located in the southern quadrants.

Like so much of amateur astronomy, I will forever be grateful for the time and effort given by others to help those like me pursue our hobby. The material, videos and responses to my forum queries on guiding have as usual been nothing short of outstanding and very, very helpful. It’s still been difficult to get going but without the help and support of others it would be a complete non-starter. In this respect I’d like to pay credit to SGL and the Open PHD Guiding forums.

Armed with this knowledge I have since undertaken a few sessions using PHD2 with reasonable success, achieving exposure times of 5-minutes and more. Changing conditions and different objects make it necessary to continually finesse guide settings throughout the night and between nights and it’s already obvious that there’s much more to learn. Such adjustments are not always linear or empirical in nature and will often only come from gut feel (experience).

I have chosen to use ASCOM pulse guiding, though my equipment also has ST4-ports which I had initially intended to use due to its apparent simplicity. I am unable to argue the pros and cons of each method but there seems to be an overwhelming preference for pulse. What I do understand (I think) are the greater subtleties that can be obtained with the pulse guiding technique and in particular, the co-ordination it provides with ASCOM, thereby ensuring PHD and the mount communicate with each other to provide essential directional information as well as guiding. I am still investigating the impact of various BRAIN settings but through trial-and-error have progressed since my first guiding session.

First Pass: early guiding results 30th August 2016

Getting better: most recent guiding results 12th September 2016

Calibration of PHD is frustratingly slow and it seems that even after successfully completing the RA-procedure can still fail during the subsequent DEC / backlash clearance. After calibration use of the PHD Guide Assistant can then provide more help in achieving the best settings for the given set-up and conditions, though it is also very slow. However, once completed PHD is fantastic and so far has run well during the night, even when changing objects. Furthermore, I’ve also studied and experimented with the PHD Drift Align tool and am hopeful that by using this I may soon be able to both dispense with SynScan altogether and improve polar alignment, hitherto my imagining nemesis as I cannot see Polaris from my location – a very exciting prospect – what’s not to like?

Starting a sequence of experimentation I chose a familiar but hitherto difficult DSO object to image that should benefit from longer exposures. Having by now reached late-summer / early autumn, there were a few old favourites around such as the Veil and North America nebulae but for these trials I decided to go for the low hanging fruit of M27 or Apple Core nebula AKA Dumbbell nebula.

My previous image of M27 in August 2014!

With limited success I imaged this planetary nebula in my early days of astrophotography but with its 8.0’ x 5.6’ size and apparent magnitude of +7.5, I found it difficult to obtain good detail and colour. However, even without guiding the improved set-up and alignment produced better results at 3-minutes and with +5-minute guided exposures the images immediately showed very noticeable improvement.

The images were taken on four different nights starting on 23rd August and finished on 8th September, during which time the sky was clear and the weather warm with very low humidity, though by the end seeing conditions had started to deteriorate due to the impact of the emerging 1st quarter Moon. All images have been cropped to the same size of 700 x 500 pixels or 2% of the original FOV i.e. an object size of about 0.20%! Given this very small size M27 really is at the limit of the GT81 telescope.

m27-comps-paintfile-cropped

Strictly speaking the images are not fully comparable as the aggregate exposure times are not equal but nonetheless I think the results demonstrate the positive impact of guiding. The final two images are guided but do show greater star distortion, particularly at 8-minutes. I suspect this may be due to the period over which the mount was left outside and would probably have benefited from some alignment tweaking before imaging re-commenced – lesson learned; the severe cropping ratio has also magnified any problems that would probably be less obvious in a larger widefield image. There’s obviously room for improvement but I’m very happy with these early results which I can hopefully now build on.

M27 Apple Core Nebula – my first and favourite guided image | William Optics GT81 + 50mm guide scope & 10-point EQMOD-ASCOM star alignment model | modded Canon 550D + field flattener & Starlight Express Lodestar X2 guide camera | 3 x 300 secs @ ISO 1,600 & full calibration, 3.3% cropped image| 30th August 2016

Unfortunately there is some downside to the longer exposures obtained from Fairvale Observatory: potentially more aircraft tracks and cloud plus more extended imaging time is unavoidable but overall it is, as expected, a major leap forwards for my astrophotography. There’s still much to learn and improve with the technique but for now I am delighted to say that after nearly two years I am at last successfully guiding – would you Adam & Eve it?

Dark Matters

September 7, 2016 by grahamrob in Deep Sky Objects, Equipment, Imaging, Universe and tagged Aquila, Dark Nebula, DSO Imaging, Einstein, Hitchhiker's Guide to the Galaxy, Photography | 2 Comments

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After some months I have just finished reading Walter Isaacson’s outstanding biography of Albert Einstein. I don’t know how the author, as far as I know a scientific layperson and writer of the equally good Steve Jobs biography, is able to pull together Einstein’s thoughts and theories in such an engaging and comprehensible manner that provides both insight and understanding into his scientific thinking, life and personality.

Besides the implications his work already has for nuclear physics and astronomy, even in the 21^st Century we are only just starting to understand and confirm concepts that were either predicted or implied by his work of uniquely pioneering theoretical physics in the early part of the last century – much of which is still difficult even to comprehend, let alone understand. In the world of astronomy two of Einstein’s predictions have only recently been shown to actually exist, with very exciting implications for our understanding of the Cosmos: gravitational lensing and earlier this year, confirmation of the presence of gravitational waves – ripples in the fabric of space-time itself!

Einstein vindicated: In the constellation of Cetus, the galaxy cluster Abell 370 abounds with evidence of gravitational lensing – imaged here in 2009 by the Hubble Space Telescope

During his early work Einstein battled with 19^th Century scientists who continued to believe in the presence of the so-called ‘aether’, as proposed by Isaac Newton in 1718 – an undefined substance that supposedly filled the void in space and was responsible for the transmission of electromagnetic and gravitational forces. Subsequently Einstein’s Special Theory of Relativity was able to explain such effects without the presence of the aether but there remained problems that were finally borne out in 1924 by Edwin Hubble’s evidence that contrary to the prediction of Einstein’s work and previous astronomical theories, the Universe was in fact expanding. However, though serious these observations did not prove to be the end for Einstein’s work, merely the beginning of even more incredible theories that have even greater and more profound implications for the Universe.

History_of_the_Universe.svg.png

As a geologist by training, my background is scientific and I continue to follow with interest related developments across a broad spectrum. My perception, which I think is justified by facts, is that we are again experiencing something of a quantum change in our understanding of physics at the moment. No ‘new Einstein’ has yet emerged, though Stephen Hawking perhaps comes close and there are many bright minds still struggling to understand what it all means – certainly we seem no closer to a unified theory. At the ‘very small’ scale the increase in particle types since I last studied science in the 1970s is staggering, recently culminating in confirmation of the Higgs boson at the Large Hadron Collider (LHC) in Geneva; almost certainly there’s more to come from the LHC but I’ve already lost track (no pun intended) of what makes up matter.

330px-CMS_Higgs-event

In the meantime, ever since Hubble’s expanding Universe bombshell, the world of physics has struggled to provide an explanation of what’s happening, except to say that for expansion to happen 95% of the Universe must consist of stuff we don’t know about, that is arbitrarily (and misleadingly) called Dark Matter (27%) and Dark Energy (68%), which have theoretical properties of mass and energy that would explain why the Universe is expanding; I find this exciting and even amusing.

Our earliest view of the Universe – the Cosmic Microwave Background, formed some 380,000 years after Big Bang 13.8 billion years ago.

As I get older I look upon the world with increased wonder and ask all the same big questions as everyone else. I still find science itself exciting as we continue to unlock nature’s wonders but have increasingly had a suspicion that despite the incredible discoveries made by mankind, we are really only scratching the surface of what’s going on. The prospect that there is still so much we do not know also provides many possibilities for what is really happening; a consoling thought as I move towards old age! I believe it’s humbling for science that they (we) only know what 5% of what the Universe is made of. Notwithstanding, like Deep Thought’s answer to the question “what’s the meaning of life the Universe and everything?” in Hitchhiker’s Guide to the Galaxy (answer = 42), it will keep thousands of scientists, their computers and the media gainfully employed for many years to come. In the meantime, perhaps I can already help them?

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Early on in my astroimaging odyssey I discovered an interest in Deep Sky Objects, in particular nebulae. I find their very nature beautiful, as the birthplace of new stars and matter itself their science is also fascinating – as Moby puts it We Are All Made of Stars. There are numerous types of nebulae of equally diverse origin, with a complex variety of delicate forms that can be both enthralling and beguiling. Generally they are made of gases and dust that emit types of light that often cannot be properly seen with the naked eye and only captured by photographic methods using various sophisticated imaging techniques, such as modified cameras or narrow band filters; their very elusiveness is part of the attraction. I have been fortunate to photograph a number of these features and never get tired of their science and beauty. However, there are other types of nebulae that are quite different.

Whereas the ‘common’ nebula is fundamentally based on activity that results in the emission or reflection of light, their other ‘ relations’ are the result of a quite opposite process. In this case so-called dark or absorption nebulae are clouds of dense interstellar dust that obscures or scatters light from nearby objects behind, such as stars or emission and reflection nebulae, resulting in large, unusually dark patches in the sky. I’ve imaged a few of these features before, where in the case of Orion such a process has produced Barnard 33, better known as the Horsehead Nebula – a dark interstellar dust region in the shape of yes, a horse’s head. Recently I set out to image another less famous but equally exciting dark nebula.

Other than resorting to solar astronomy, the period of summer sometimes seems like something of a barren period, further compounded by short nights and the absence of astronomical darkness. Notwithstanding, look closely and there’s plenty happening and, if you’re lucky, it’s possible to work into the night enjoying the warmth of the season too; I’ve recently been able to stay out in a shorts and T-shirt until past 3.00 a.m. – compare that to January – apart from the comfort there’s also no sign of the astronomer’s enemy, dew. This year my wife has grown and strategically placed two night flowering plants close to my equipment, which on warm evenings produce pleasant aromas that waft across Fairvale Observatory whilst I’m working. What’s not to like?

Night Phlox (Zaluzianskya Capensis). Though quite this small plant produces a strong smell of violets at night.

Nicotiana Alata. This large plant produces a strong, fragrant smell.

Whilst there’s no Orion (though it has made an appearance in the east from at about 3.00 a.m. since late August) or Taurus (also rising shortly before Orion) with all their iconic features, instead the summer arm of the Milky Way passes across the sky from about 8.00 p.m. presenting numerous opportunities of its own in the early part of the night.

Aquila b142

This time my targets were Barnard 142 & 143, located just west of the star Tarazed in the Aquila Constellation. Roughly equivalent to the full Moon in size distance and some 2,000 light years away, both are dark nebulae which viewed together against the dense background of stars in the Milky Way clearly make the shape of the letter E – shown first below in inverted colour.

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Previously I’ve been too busy looking for the more conventional DSOs but at some 30 arc minutes, the E Nebula – as it is known – is another excellent imaging target for the William Optics GT81 field-of-view.

E Nebula, AKA Barnard 142-3 in the Aquila Constellation. William Optics GT81 FD & modded Canon 550D + 0.80x Field Flattener | 15 x 180 sec @ ISO 1,600 | 26th August 2016

E Nebula, Barnard 142-3 Dark nebulae

It turns out there are many such dark nebulae, so I hope to be imaging others in the future. I wonder what Einstein would have made of these and moreover, the hypothesis of Dark Matter & Energy? It seems that once again he may have foreseen such developments and their possible existence may ironically even be found to relate to the cosmological constant used in his original General Theory of Relativity.

Playing poker with the heavens

August 23, 2016 by grahamrob in Imaging, Solar system, Viewing and tagged Perseids, Perseus, Photography, Solar system | 1 Comment

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It’s that time of the year when Earth ploughs its way through the tail of comet Swift-Tuttle, resulting in a the Perseids meteor shower. The name is derived from the location of the radiant point within the constellation of Perseus and Greek mythology’s reference to the sons of Perseus. Such are the orbital paths that Earth’s encounter with the comet occurs around 11^th to 13^th of August each year and can provide an enjoyable spectacle as the meteor particles rain down through atmosphere.

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Travelling at some 37 miles-a-second, the sand-grain size particles literally burn up in the blink of an eye, with the energy created producing a bright path of the light path that very briefly shoots across the night sky, sometimes green or red coloured. Some 16-miles in size, from time-to-time the comet itself actually passes nearby to Earth during its orbit around the Sun, last time being in 1992 and the next in 2126.

Perseid ZHR 2016

Whilst the timing of our annual encounter can be predicted with good accuracy, a sight of each individual meteoroid particle is entirely down to chance. Over a period of two or three days the frequency (Zenithal Hourly Rate or ZHR) may vary from a few tens to a few hundred, depending on which section of the comet’s tail Earth is passing through. Of course, observation requires a clear sky – something that’s been notably absent here at Fairvale Observatory for some time now. Notwithstanding, this year there were three consecutive clear, dark, warm nights, which occurred shortly after a new Moon that provided excellent Perseid observing opportunities.

Viewing is a matter of lying back in a suitable garden chair looking up towards the radiant position, which starts in the north east then moves to the south during the night and just waiting. This year peak Perseids were on the evening of 11^th/12^th August between about 11pm and 1am, during which time we probably saw between 20 to 40 hits an hour; the previous and subsequent evenings were also quite good, though with slightly less hits. Such is the randomness of each meteoroid hit that in practice Perseid trails occurred all over the sky and were easy to miss if outside the peripheral vision. However, overall it was a very good and enjoyable show but probably not as good as that from the ISS.

At first this looks great but look again, it’s an aircraft trace – living next to Gatwick airport doesn’t help. The giveaway is in the next shot which shows the track continuing i.e. too long and too far for a meteoroid.

At the same time using the Canon DSLR and an ultra-wide lens, I also attempted to image the Perseid shower. On the first night using Vixen Polarie tracking, set towards the radiant position and on the second night pointing east, without tracking. Control was via an intervalometer, with camera settings at ISO 800, 20 or 14 second exposures, and 5-second shot intervals. Even with such a high incidence of meteoroid hits, obtaining a photograph was still very difficult; mostly the strikes occurred outside the field-of-vision or sometimes in the 5-second pause. In total I shot over 300 images but obtained just two Perseid hits and more than a few plane tracks! Even with good preparation and clear skies it really is a case of chance but I was nonetheless pleased to have my share of luck this time and look forwards to another opportunity this time next year, weather permitting.

Gotcha – the real thing: ISO 800 @ 20 seconds with tracking.

Only just! This time the Perseid is just sneaking out of view at the bottom of the frame: ISO 800 @ 14 seconds, without tracking.

Talk The Talk

May 25, 2016 by grahamrob in Equipment, General Astronomy, Imaging, Software, Widefield Imaging and tagged DSO Imaging, Moon, Nebulae, Photography | Leave a comment

“He who can, does. He who cannot, teaches.” 1903, George Bernard Shaw

At the end of last year I was contacted by a member of the Aperture Club, a photography group based in Purely – Surrey, who had come across this website and asked if I could give a presentation to the club’s members on astrophotography. Ordinarily I might have rejected the request – after all what do I know about astrophotography after only 18-months – but then again why not? Once I sat down and compiled some initial thoughts it was surprising just how far I had come and learnt already, albeit with still a long way to go. In the end I agreed and decided to take a two-fold approach to the talk: (i) a basic overview of astrophotography, and (ii) in this context my personal journey so far.

TTT Cover

The final structure adopted was like this, which I hoped would be both technically and aesthetically engaging and provide some insight into the challenges for astrophotography when compared to their day-to-day terrestrial pursuits:

Types of astrophotography
Astrophotography Methods
Light
Telescopes
Imaging
Cameras
Image Capture
Processing
Post Processing

I gave my talk to the club at the end of March, which lasted about 1-hour and I believe was well received; there was a good turn-out and subsequent Q&A session – which is always a good sign. I had also been asked to compile some related tasks for the members to undertake afterwards and after a break presented a second, shorter talk on some possible assignments. Copies of the talks can be accessed via the links here:

Astro Lecture PDF

Astro Assignments PDF

I would not be so arrogant to undertake such a presentation to other astrophotographers, at least not yet, but enjoyed introducing members of the Aperture Club to my hobby. Furthermore, through compiling the presentations I benefited from the process, which required me to think and understand the subjects more thoroughly than I might otherwise have done, making me think that Shaw was wrong. Good teaching requires a good understanding of the subject, the skill to impart that knowledge to the audience and the ability to apply the knowledge. I’ve previously walked the walk and in this instance I’d like to think I was able to talk the talk – I found the experience rewarding and I hope members of The Aperture Club did too?

The Sky’s The Limit

April 22, 2016 by grahamrob in Astronomy holidays, General Astronomy, Imaging, Widefield Imaging and tagged Arizona, Moon, Orion, Photography, Utah | 2 Comments

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Imaging the Milky Way is a popular objective that has so far eluded me, mainly as I suffer from bad light pollution here at Fairvale Observatory. Embarking on a trip to the Southwestern USA recently where dark skies abound, I therefore had high hopes of at last achieving this goal but alas it was not to be and will have to wait for another day.

The trip of a lifetime

As a geologist I have often visited parts of Nevada, Colorado, Utah and California but never the famous sites of the Grand Canyon, Monument Valley, Glen Canyon (Lake Powell), Bryce Canyon and Zion National Park, which this time formed the trip of a lifetime.

Alvan Clark & Sons 24″ refractor telescope at Lowell Observatory, Flagstaff, Arizona

First stop was after flying into Las Vegas was Flagstaff, home of the Lowell Observatory, where Pluto was first discovered and amongst others houses a magnificent 24-inch Alvan Clark & Sons refractor telescope built in 1895, which I hoped to use for viewing at the observatory’s nightly public sessions. Unfortunately this was not to be as the sky remained resolutely overcast throughout the evening, despite good conditions earlier in the day. Notwithstanding, the observatory is a fascinating place and still remains an important centre of modern astronomy studies; the adjacent town of Flagstaff is also home to the Department of Physics and Astronomy at the Northern Arizona University.

Final notes and paper published by Percival Lowell postulating the existence of a Planet X beyond Neptune, later confirmed by Clyde Tombaugh at Lowell Observatory in 1930 and named Pluto

About 40-miles east of Flagstaff is the site of Meteor Crater, the best preserved meteorite impact crater on Earth. Nearly one mile in diameter and over 500 feet deep, the 50,000 year old crater is very big and very impressive. There’s a lot to like about Flagstaff if you’re into astronomy!

Meteor Crater, Arizona, USA

The Holsinger Meteorite: the largest remaining fragment of the 45 metre meteorite that created Meteor Crater

Moving on to the next stop at the Grand Canyon did not disappoint but staying just outside the park the location suffered some light pollution, compounded by cloud during the evening, thus prohibiting any imaging.

The incomparable Grand Canyon by day. Whilst we stayed around for sunset, unfortunately light pollution and cloud later prevented further nightscape imaging.

As a more remote location I had always envisaged that next stop at Monument Valley would be my first real opportunity to undertake some night imaging, for which purpose I had taken along the Vixen Polarie and a tripod. In preparation I had previously studied the sky in this part of the world using Cartes du Ciel, which indicated that the Milky Way would be well positioned during my visit; being 35^o latitude and 5,000 miles west of Fairvale Observatory meant that the sky was similar to that viewed in the UK three months ago and therefore included my favourite constellation Orion. Unfortunately I had overlooked one problem and my long-time nemesis, the moon.

The night sky from Lowell Observatory on 30th March 2016 – no Moon.

10-days later: night sky from Lowell Observatory on 10th April 2016, now with the Moon!

I was in the USA from 5^th to 17^th April but for some reason had modelled the sky in Flagstaff on 30^th March. It turned out that between then and 10^th April, when I was in Monument Valley, the by now half-moon had moved into the night sky and ruled out any chance of seeing or imaging the Milky Way. Of course, even if I had correctly identified the problem beforehand there was nothing I could do about it but it was still frustrating. Notwithstanding, it was a clear sky and not to be defeated turned to Plan-B, which instead took advantage of the moon’s position and in my opinion turned out quite well.

Monument Valley by Day: left to right – West Mitten, East Mitten & Merrick Buttes

Despite the remote location at Monument Valley there was noticeable light pollution from the hotel and ancillary facilities. However, being on the ground floor it was possible to set-up adjacent to the room’s balcony looking east, which was fortunately in the building’s own shadow, thus enabling a sequence of images to be taken of the night sky set against the buttes that typify this region. UnfortunateIy I overlooked setting the Vixen Polarie to half-sidereal tracking speed, which subsequently resulted in a blurred landscape when stacked but the original subs capture the buttes in some detail, themselves illuminated by the moon’s light = result!

Monument Valley by Night; order of buttes same as above. Canon 700D + Sigma 10mm wide-angle lens | 15secs @ ISO 6,400 | 10th April 2016

Monument Valley at Night – mulitple stacked shots: Sidereal tracking results in better sky but blurred landscape. Canon 700D & 10mm Sigma wide-angle lens | 20 x 15 secs @ ISO 6,400

Three days later I was in Bryce Canyon, the location of extraordinary geological features called hoodoos, which are the result of unusual and extreme weathering of the limestone cliffs found there. The land forms consist of thousands of various sized pillars of white and red limestone, seemingly lined up like soldiers along miles of the east facing limestone cliff face. Once again I used the moon to illuminate and capture the scene, this time using half-sidereal tracking. The result is somewhat haunting in nature but shows almost as much detail into the far distance as during daytime; I still find it incredible how sensitive the camera’s sensor is in gathering available light at night when extending exposure times and / or turning up the ISO setting.

Bryce Canyon at Sunset Point by Day

Bryce Canyon at Sunset Point by Night: Canon 700D + Sigma 10mm Wide-angle lens | 15 secs @ ISO 3,200 | 13th April 2016

It is clear I have much to learn about the deceptively simple nightscape photography using the Vixen Polarie but it is equally clear that the equipment provides significant potential and I look forwards to catching the Milky Way one day when the sky is clear and the moon absent. Notwithstanding the disappointment of missing out on the Milky Way this time, in the spectacular big country of Southwestern USA the sky’s the limit and I hope to go back again one day.

Too much light pollution perhaps? Even in the Big Country of the Southwestern USA getting the right conditions for astrophotography remains a gamble!

Fairvale Observatory Part-3, Progress: modded DSLR, computer control, autoguiding etc.

April 4, 2016 by grahamrob in Autoguiding, Equipment, General Astronomy, Imaging, Software and tagged DSO Imaging, Photography | 4 Comments

It’s been a while since I last took a look at developments here at Fairvale Observatory (Part-1 & Part-2) and looking back it’s pleasing to see that progress has continued with positive results. After acquiring the William Optics GT81 refractor and AZ-EQ6 mount in 2014 I have been experimenting and enjoying the equipment’s significant abilities until recently but have now embarked on some new, potentially important improvements that hopefully will result in significant breakthroughs.

At the start perhaps the biggest problem for imaging was polar alignment, made very difficult here as my house almost completely obscures Polaris. It took some time but I’ve now overcome this by using the Synscan handset polar alignment technique, which now enables me to achieve an accuracy of just a few arc-seconds and has led to a significant increase in imaging times of at least 180 seconds.

With the short focal length of the fast William Optics this level of alignment error works well and I’ve been pleased to obtain decent images of larger DSO features such as the Great Orion, Rosette and Veil nebulae i.e. near / middle distance objects, ideally at least 1^o in size with an apparent magnitude of +7 or better. Once I’ve exhausted all these targets, and I have fortunately been discovering more and more, it’ll be time for another telescope!

The small things matter too and in this regard I’ve added a number of useful items:

Made a solar filter and finder tube for the WO GT81;
At last, I recently collected the cables together into two looms;
Purchased a 12mm reticle to aid alignment;
Astronomik CLS light pollution clip filter;
Photoshop – an old version but I’ve been successfully using it for processing.

The set-up has become a lot tidier and logistics made easier by collecting the power and camera cables into two separate looms (camera loom not shown) and permanently attaching the HiTec Astro control cable to the mount – why didn’t I do this before?

More significant additions that I’ve already reviewed include a modded Canon 550D DSLR, which together with improved tracking has revolutionised imaging and a recently a Vixen Polarie, that has transformed widefield photography and added a new dimension – transportability. It’s early days and I have not really got to grips with the Vixen Polarie yet but initial use suggests it’s going to be a very useful addition and potential game changer.

At the end of last year in Reflections I outlined my goals for 2016 and I am pleased to say that I have at last just started to establish the equipment and software to start autoguiding, the holy grail of astroimaging that when fully working should enable me to achieve exposure times significantly greater than present – which is likely to be at least another couple of months. For a while I have been successfully using EQMOD /ASCOM combined with Cartes du Ciel for tracking. There were some initial connection problems but now using a HiTec Astro EQDIR adapter and a better quality USB cable seems to have improved this matter; I’ve also recently secured it to the tripod making the set-up more stable and aiding logistics. I still polar align with Synscan before switching to EQMOD-Cartes du Ciel for additional star alignment, slewing and tracking.

Using EQMOD-Cartes du Ciel makes slewing to any chosen object much easier than Synscan but its use has introduced another operating problem. After slewing to a chosen object or star it is never exactly centred and some manual fine alignment is almost always necessary at this point. The problem is that this requires being at the eyepiece, which of course is not located by the computer, which means frequent toing and froing between the two locations and a lot of guesswork when adjusting the mount from the computer. In reality this is not very practical and I have therefore just purchased a gamepad that links wirelessly to the computer and allows mount adjustments to be made when at the eyepiece. It’s not quite set up yet but nearly and I’m impressed; ASCOM even allows you to add WAV files that speak to you when making changes – sounds like a gimmick but when in the dark with lots of items to attend to it is actually very useful and will hopefully reduce the possibility of making mistakes.

Wireless gamepad provides extensive control of critical alignment functions without being at the computer: front x4 buttons are assinged to set various slew rates, the mount-telescope can be directed either via the rear (shown right) joystick or POV buttons on the right, button-1 parks and button-2 syncs. Other buttons have yet to be allocated.

It had been my intention to use the ZWO ASI 120MC webcam for guiding, in fact I upgraded to this at the time of purchasing in 2014 for this very purpose as it has a specific port for ST4 autoguiding directly with the mount. However, very recently a Starlight Express Lodestar X2 guide camera came up second-hand and being widely acknowledged as one of the best guider cameras available I couldn’t resist! Of course, despite its pedigree like most things with astroimaging it has not been that simple to get working.

Starlight Express Lodestar x2 Guide Camera can be used either via the mount’s ST4 port or via ASCOM and the computer for pulse guiding – I’m doing the latter.

Despite being a dedicated guide camera with high operating specifications, at first I could not obtain any sort of image to prove it was even working but by transferring the lens from the ZWO camera and fiddling with the software I eventually got an image, phew! It’s important to say here that for guiding it is also necessary to use suitable guiding software and I‘m inevitably using PHD2, which itself is full of wonderful features and mischief that I am at the early stage of learning and trying out with the camera.

William Optics 50mm x 200mm with focus tube and Lodestar guide camera – after lengthy experimentation, insertion of a x2 Barlow barrel eventually achieved focus.

At this early stage the other inevitable obstacle has been achieving focus. The William Optics GT81 telescope conveniently comes with its own guidescope rings that elegantly form an integral part of the OTA shoe attachment. With guiding as a long term goal, I therefore obtained the matching 50mm William Optics guidescope at the time of purchasing the main telescope, which until now has been sitting in its box as I built up the courage to put it all together and attempt guiding.

The black art of autoguiding and infamous PHD2 screen; I have just for the first time got the camera and PHD2 working together: focussed, calibrated and guiding. The nature of the blue (RA) and red (DEC) traces indicates there’s still much to learn but at least it’s working and holds much promise for future imaging!

As a matching guidescope and a dedicated top-of-the-range guide camera I assumed it would all fit together and with a little adjustment focus could be obtained, right? Wrong. I played with the camera’s position but failed to get any idea where the point of focus was. Next time I initially had the same result but by now knew that the camera was working so persevered and by using the barrel from a x2 Barlow with the lens removed eventually found focus, about 2cm back from the maximum position achieved using just the guidescope + focus tube and camera. I know that there are many makes of equipment and permutations but surely a matched guidescope and standard, best-in-class guide camera should be designed to work together from the outset?

So what’s next? I am hoping that after a few more sessions with the guide scope and PHD2 I will able to start autoguiding properly. However, two years of astronomy and an early look at PHD2 tells me it probably won’t be that easy. Notwithstanding, two years of astronomy also tells me that perseverance is essential and usually pays off. Watch this space!

A Wider Perspective

January 23, 2016 by grahamrob in Deep Sky Objects, Equipment, General Astronomy, Widefield Imaging and tagged DSO Imaging, Nebulae, Orion, Photography | 3 Comments

I like to think and operate at both ends of the spectrum: sometimes considering detail and its implications and often exquisite beauty, whilst on the other hand taking a wider view will often provide broader insight and answers – notwithstanding, I am usually drawn towards the latter. There was no shortage of scope for such thoughts in my career as a geologist and now as my hobby in astronomy. I have become fascinated with parts of the Universe and captivated by imaging them: galaxies, nebulae, star cluster etc. but the wider view is often even more astounding and perplexing.

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My nascent astroimaging has already produced some rewarding photographs, which using the fast William Optics GT81 refractor has enabled me to obtain images of up to 3^o FOV. In fact this became something of a theme last year, successfully imaging features such as the Sadr Region and as they say, one thing has led to another. Wanting to image even wider views there’s mostly only one alternative, using a camera and lens. I’ve tried this before, on a tripod and fixed to the ALT-AZ EQ6 mount but with mixed success. Meanwhile, I came across excellent pictures taken using lightweight tracking mounts on a tripod and as a result the way forwards became obvious; after scanning the Classified advertisements online for a while I was fortunate to find and purchase a second-hand Vixen Polarie mount last September.

Probably my favourite object, which can rightly be considered the signature image of the winter night sky and is therefore around at the moment, is the constellation of Orion and especially its numerous and often exciting constituent parts: M42, Horsehead & Flame Nebulae etc. After waiting for weeks for the clouds to clear, I briefly got a chance to image Orion using the Vixen Polarie early in November, whilst at the same time using the WO GT81 to obtain yet another picture of the irresistible Great Orion Nebula M42.

Orion’s Sword – including the wonderful Great Orion Nebula M42 et al : WO GT81 + modded Canon 550D & FF | 14 x 180 secs @ ISO 1,600 | 9th November 2015

The Vixen Polarie is a deceivingly simple and well-made solution to obtaining long exposure images of the wider night sky using a camera and lens. As stability remains essential for the mount and camera to operate at their best, I also purchased a decent Manfrotto tripod and suitable ball heads to attach the Polarie. After that it was simple, well not quite! Trying out the Polarie at the same time as using the GT81 and being first time out was a mistake. I fumbled setting up the equipment and initially even forgot to turn on the tracking, leaving only a short time to grab a few images before the clouds rolled in once again! Not surprisingly the results were mixed and I was left frustrated. With continuing poor seeing conditions, it was to be a further month before I had an opportunity to properly use the Vixen Polarie again – this time with a new Sigma 10 – 20 mm ultra-wide angle lens I had just purchased.

Vixen Polarie & Canon 700D + 18 – 55mm lens | 19 x 60 secs @ ISO 800 | 9th November 2015

Having by now spent more time looking at the manual (we all get there, in the end) and concentrating on imaging using only the Polarie, this time I was able to achieve a good set-up and remembered the correct sequence of operation. As the mount sits high on the tripod I am just about able to see Polaris in a small gap between the roof of my garage and house, something hitherto impossible when using the lower positioned AZ-EQ6 mount. As a result I am able to achieve a reasonably good visual polar alignment, though a polar scope made specifically for the Vixen Polarie would improve this further; probably something for another time? Nevertheless, such an alignment at Fairvale Observatory is a first and was a major breakthrough that has already permitted exposures of 4 minutes and could probably go to 5 to 6 minutes or more.

The high position of the Vixen Polarie on the tripod provides an otherwise elusive view of Polaris between the garage / utility room and the main house for polar alignment, at last! Alignment of the mount is carried out by viewing through the hole in the top right of the Polarie – better alignment can be achieved by using a polar scope which fits through the middle of the Polarie mount.

Once polar aligned, fixed on the front of the Vixen Polarie the camera then rotates to follow the celestial sphere and chosen object in order to achieve a sharp image with long exposures. For this purpose there are 4 tracking rates: sidereal, half sidereal, lunar and solar. With no interesting foreground here I concentrated on the sky by using the sidereal rate; for more scenic shots with the landscape incorporated, using half-sidereal provides a compromise in order to achieve a non-blurred image of the sky and landscape, though this method is inevitably limited to shorter exposures than sidereal.

Vixen Polarie mount on Manfrotto tripod – a lightweight, portable tracking method for widefield astroimaging

Vixen Polarie – close-up showing x2 ball head fittings

Vixen Polarie – tracking speed settings

VP Dial

Vixen Polarie with DSLR attached & ultra-wide lens

I have adapted a somewhat basic red dot finder to fit on top of the DSLR camera using the hot shoe, which was immediately helpful to accurately locate the desired target area. However, as previously experienced, once again achieving focus proved quite difficult, basically requiring just trial and error; I intend to look into a more efficient method but in the absence of a Bahtinov mask this is likely to be the best technique for now. A laptop can be used for image capture but maintaining the themes of portability and simplicity, I successfully used an intervalometer to control exposures.

Whilst initially my target was the Orion constellation, I’ve long held the ambition to image Barnard’s Loop, a much larger and elusive feature surrounding the constellation and more difficult to photograph. I had tried this before last January with limited success but ever since acquiring the Vixen Polarie this has been my No1 imaging goal.

Orion Constellation 220115 Stacked1L2C3GX (Large)

The Orion Constellation & Barnard’s Loop (up / north is left) : AZ-EQ6 Mount + Canon 550D & 200mm Telephoto | 180 secs @ ISO 1,600 & calibration | 22nd January 2015

Unable to see with the naked eye, only using long exposure photography unveils the majesty of Barnard’s Loop, an emission nebula to the left (east) of the Orion constellation. Shaped as a large-C, the loop completely encompasses the eastern side of the constellation and is thought to be a recent supernova front moving out from Orion and illuminated by stars from within the nebula, as well as part of the Orion Molecular Cloud Complex. Discovered and named after astrophotographer E. E. Barnard in 1895, at some 14^o or 300 million light-years across Barnard’s Loop is enormous; however, the entire Molecular Cloud is about 30^o in size!

pleyades31_02

The Orion constellation was originally conceived in Greek mythology as the Hunter, pursuing Taurus the Bull to the west, with the stars tracing out a shape of a hunter holding a shield and club in each hand, a belt around the waste with a sword attached. What they could not have known at the time is that he also has a head, in the form of the Lamda Orionis Nebula (Sh2-264), located centrally and above Betelgeuse and Bellatrix.

Barnard’s Loop & Lamda Orionis Nebula : Vixen Polarie & modded Canon 550D + Sigma UWA @ 20mm | 11 x 240 secs @ ISO 1,600 + darks | 7th January 2016

I was able to image Barnard’s Loop on 7^th and 14^th January; at ISO 1,600 the first images showed the Loop but certainly left room for improvement, as a result I shot the subsequent images at ISO 800 and obtained a noticeably better outcome – though I had to push post processing to reveal the features. The Loop and head are clearly evident but I’ve been intrigued to see other objects also revealed, albeit without the detail obtained with prime focus imaging using the telescope: Great Orion Nebula, Horses Head & Flame Nebulae and surprisingly on the left (east) of the Loop the Rosette Nebula. Looking at other’s images of Barnard’s Loop it is clear that I will need to take significantly more subs to properly reveal the full beauty of this wonderful and very large feature – dark skies would be nice too – but for the moment I am pleased with my first outing using the Vixen Polarie, which holds great promise for capturing a wider perspective of the Universe.

Barnard’s Loop & Lamda Orionis Nebula + Rosette Nebula on far left : Vixen Polarie & modded Canon 550D + Sigma UWA lens @ 20mm | 14 x 240 secs @ ISO 800 | 14th January 2016