Reflections 2020

December 29, 2020 by grahamrob in Autoguiding, Broadband, Deep Sky Objects, Equipment, Imaging, Narrowband, Nebula, Processing, Software, Viewing, Widefield Imaging and tagged PixInsight, Starnet++, Topaz Denoise AI | Leave a comment

After starting astronomy in 2014, Watch This Space (Man) was launched shortly thereafter as a personal record of my then nascent astronomy journey. Apart from the main blog about my progress or otherwise, links to other astrophotographers, astronomy tools, astronomy weather, scientific papers etc. can also be found on this website; I was suprised to see that to-date 152 items have been published on this site.

I always like to hear from others – comments, questions, help or just to say hello – and can be contacted via: graham.s.roberts@gmail.com or just leave a comment at the end of any item if you prefer.

Vistor map 2020: In this most difficult of years for everyone, it’s especially heartening to see so much interest from all corner’s of the world and hope to see you and others again in 2021 – Clear Skies!

REFLECTIONS is a review of my astronomy and astrophotography during the past year, together with some thoughts on possible future developments.

2020 Overview, Images & Goals for 2021

For the world 2020 was a year like no other. Notwithstanding the obvious problems and dire consequences of Covid-19 for everyone, there have been surprising benefits for astronomy. Although I am retired, under lockdown there was even more time available for hobbies. Furthermore, as I live close to Gatwick and Heathrow airports + underneath numerous high altitude long-haul overflight paths, a massive reduction in air travel resulted in a very obvious improvement in seeing conditions, which was confirmed by guiding results. Located in a Bortle 5 to 6 area I ordinarily achieve at best average RMS error guiding of 0.90” to 1.50”/pixel, guiding improved markedly during lockdown to between 0.50” to 0.75”/ pixel. Of course such seeing conditions also resulted in better quality imaging itself and on a number of occasions I was able to achieve integration times of 10-hours or much more over a number of nights. The result was better images but less of them and inevitably, a lot more cloud throughout the rest of the year!

Having previously got to grips with plate solving, using the new CdC planning function I intended to develop the use of mosaics this year. However, such is the weather in the UK (see above) that it’s obvious to me that creating mosaics is probably not the best use of what imaging time we get. Undeterred, during January I planned and shot a 15x panel mosaic of Barnard’s Loop in Ha-wavelength. Unfortunately the unpredictable occurrence of patchy cloud invalidated some of the panels, though I was finally able to compile a 7x panel mosaic of the upper easterly section of Barnard’s Loop – see below. Notwithstanding, there were lessons learned: (i) restrict mosaics to one or two panels and / or (ii) where wider view images are required use a wide FOV set-up rather than a large mosaic.

Most of my other objectives for 2020 turned out to be pipedreams e.g. a new observatory or perhaps a larger telescope or dual rig. Despite this there were important developments on other fronts.

After eventually coming to the conclusion that mosaics were probably an unwise way to go considering UK conditions, it became clear that a suitable high-quality camera lens might produce similar coverage with less imaging time and hassle. Thus also inspired by the images of others on the SGL Forum using such equipment, I set out to build a new rig based around the excellent Samyang 135 f2 lens. This project remains work-in-progress but so far using the lens with a bespoke 3D printed rig and micro focuser made by Astrokraken and a modded DSLR, it’s apparent that this lens produces excellent widefield images in a relatively short time.

Initial Samyang 135 f2 set-up with modded DSLR

With the time and ‘opportunity’ afforded by lockdown throughout most of the year, I finally decided to do something about improving my processing, namely learning PixInsight. Unfortunately the rumours were correct – it is a steep learning curve and altogether a less than user friendly software. However, after many weeks of toil and expletives I’m pleased to say I can now process an entire image with PixInsight, the impact of which has been nothing less than profound. However, whilst PixInsight is an excellent processing facility, I’ve come to the conclusion that it is often best used together with other process software where appropriate for specific tasks:

Deep Sky Stacker for calibration, alignment and stacking; the equivalent PixInsight process is just too complicated and time consuming;
Photoshop can be very helpful finessing colours and stretching (Levels & Curves);
Starnet++ is useful for creating starless images, which then help to get the best from processing nebula separately before re-combining with the stars;
Topaz AI Denoise has been very effective and easy to use for noise reduction and sharpening at any point during the workflow.

This combination for processing has turned out to be something of a game changer and almost certainly was the most important astrophotography development of the year for me, which augurs well for 2021 and beyond.

Favourite Images

Continuing with the theme of less is more, I imaged just 13 objects this year – of which three were experimental & three with a DSLR – but still with a total integration time of 80 hours (2019 17 objects & 65 hours, 2018: 25 objects & 43 hours). Having worked through many of the astronomer’s favourites by now, images in 2020 consisted of: a new approach to old favourites, difficult / small objects for my equipment e.g. galaxies or less popular and widefield targets.

I’m pleased to say that most of these images turned out well and it’s difficult to choose a favourite. The so-called ‘favourites’ below therefore represent those images from this year that portray an important development in my astrophotography journey. More detailed reviews of these and all other images from 2020 can be found in specific articles that can be accessed using the links found below or via the Blog Index, located under the dropdown menu ABOUT.

Heart Nebula: Although imaged in 2018, this version has been re-processed using mainly PixInsight, thus transforming the original SHO Hubble Palette image from something rather dull to one with warm, vibrant colours, as well as much great detail – demonstrating the significant impact of my new PixInsight based processing abilities.

LBN 325: Numerous emission nebulae populate this small part of a very extensiveHII-Region, which forms an exciting LRGB image. Processing was complex and difficult, in order to bring out exciting features that abound in this spectacular but less popular area of the Cygnus constellation. Integration time of 10-hours was obtained over three nights and is my first LRGB image processed using PixInsight.

M63 Sunflower Galaxy: At 12.6’ x 7.2’and apparent magnitude of +9.3,this small flocculent galaxy in the Canes Venatici constellation is a challenge for my equipment. However, with 8 hours 20 minutes exposure over three nights in April and careful processing, the all-important detail within the galactic disc is clear. Topaz Denoise AI and Gigapixel software played an important role in maintaining the colour and delicate detail in this +50% cropped image.

Taken from last year’s REFLECTIONS 2019:

“Although you never know, I don’t see any major breakthroughs in the coming year”. Just goes to show what I know, fewer but better images were obtained in 2020:

RECORD CARD 2020

Goal	Specifics / Results	Outcome
Improve image capture	Further Improvements in overall quality + much longer integration times + better guiding accuracy = less but better images.	MUCH BETTER
*Better processing*	Using PixInsight software combined with Photoshop, Starnet++ and Topaz Denoise AI has led to major processing improvements and much better final images.	MUCH MUCH BETTER
Widefield Imaging	Initial results from new imaging rig based around Samyang 135 f2 lens were very promising but there’s more to do.	BETTER

My main objectives for 2020 were largely fulfilled (see above), so what about 2021?

Imaging: Other than maintaining the aforesaid improvements achieved over the past two years – guiding & longer integration times – two items that still need to be addressed are: (i) upgrade filters to remove star bloating and all round better images, (ii) improved focussing.

Widefield: Complete Samyang-rig build and switch from DSLR to CMOS mono camera.

Consolidate processing improvements: Whilst the move to PixInsight and other software was very successful in 2020, I’m still only scratching the surface of what’s possible.

Upgrade mono camera – there’s a new generation of colour CMOS cameras starting to appear, hopefully soon to be followed by their mono equivalents !

Hardly a year I and the rest of the world will want to remember, though more than ever astrophotography played a big role in providing relief from the trauma going on around us all.

The major increase of integration times achieved and the use of PixInsight has proved transformative for my astrophotography and will justify returning to reimage some old favourites in future years. I had often thought about upgrading my OTA to something bigger but given the lack of a permanent observatory here at Fairvale Observatory, combined with long periods of bad / cloudy weather, the penny finally dropped and I now have high hopes for the little wonder that is the Samyang 135 f2 lens when I complete its set-up in 2021.

Looking back I have to be happy with my astrophotography in 2020 but more importantly, look forwards to an even better year which holds great promise building on the positive developments of the past 24-months. Moreover, I hope for the sake of everyone that we will be able to deal with Covid-19 soon and return to something of a normal life once again. These are big ambitions and I hope that WTSM’s Reflections 2021 will record such success.

Watch this space!

ASTROPHOTOGRAPHY INDEX OF 2020

To access each blog, click on the title required below highlighted in RED:

JANUARY & FEBRUARY – Jinxed: Barnard’s Loop Mosaic (+ NGC 1333 reflection nebula & LDN 1622 Bogeyman Nebula)

MARCH – Nice but Dim: Medusa planetary nebula / Abell 21

MARCH & APRIL – Return of the Lion: Leo Triplet M65, M66 & NGC 3628

MAY – Galactic Bloom: M63 Sunflower Galaxy

JUNE – Canine Capers: M51 Whirlpool Galaxy

AUGUST & SEPTEMBER – The Big Picture: First Light Samyang 135 f/2 NAN, Cygnus & Veil Nebula

OCTOBER – Reach For The Sky: LBN 325 emission nebula

NOVEMBER – Swan Adventures: NGC 6914 reflection nebula

DECEMBER – Image Redux: HST re-processing – Pacman, Heart, Rosette, NAN & California Nebula

The Big Picture

September 9, 2020 by grahamrob in Deep Sky Objects, Equipment, General Astronomy, Imaging, Widefield Imaging | 3 Comments

I’ve been very happy with my main imaging set-up for nearly 4-years: Skywatcher AZ-EQ6 GT Mount + William Optics GT81 + ZWO1600MM-Cool mono camera. Nevertheless, thoughts inevitably stray towards the big and usually expensive question – what next? Given the said equipment, a natural move is likely to be the addition of a larger telescope to get at those faint fuzzies and I have been toying with such an idea for some time – probably another refractor in the 100mm to 130mm range. However, I’ve always been held back by a number of nagging issues:

Without a sightline of Polaris for polar alignment from the main location at Fairvale Observatory, guiding is always going to be sub-optimal – I can get away with it with the smaller William Optics but a larger aperture / focal length would be more challenging;
Being a set-up / take-down observatory each night, the increased technical demands of a larger OTA would certainly take longer and in general be more difficult to undertake – as I get older moving the mount is already taking its toll on my back;
Time is short as there’s simply no getting away from the problem we all suffer in the UK – cloud and lots of it! It’s been normal to go weeks, even months without a clear night sky and as a result last year I managed to image just 18 objects over some 27 nights, of which some were only over a few hours before the clouds rolled in;
A static observatory would help enormously but my garden is unsuitable: apart from the aforesaid problem that my house obscures a northerly view, there are also houses and substantial trees and very high hedges on all the other sides.

Regretfully I have therefore always come to the same conclusion, that unless I moved house it was best to continue with my current set-up – until now! Inspired by a fascinating thread on the Stargazers Lounge Forum the solution was blindingly obvious, or at least it was once I understood there was another way, a larger field-of-view rather than larger telescope, achieved with a traditional though far from ordinary camera lens.

As a life-long photographer on land and underwater, astrophotography surprisingly came as something of a shock, as it’s just so contrasting to the aforesaid disciplines and requires quite different technical knowledge and aptitude. Of course, I’ve often used my camera equipment to image the night sky, particularly the Milky Way and started out astrophotography using a modded DSLR but otherwise did not consider that a camera lens could form the basis for my astrophotography going forwards – then I discovered the Samyang 135 f2 lens. Moreover, looking at what others achieved matching this lens with a tracking mount and mono camera, the decision to join the Samy club was a no brainer.

Located in South Korea, Samyang Optics has been manufacturing good camera lenses since 1972. Also sold under the Rokinon brand name, the Samyang 135 f2 stands out for two reasons:

The optics of the lens are top drawer, consisting of 11-elements in 7-groups using very high quality glass;
The lens is very well suited to gathering photons with a maximum f2 aperture – though most users stop down to 2.8 in order to achieve good star shapes right into the corners.

The optical quality produces sharp image quality from corner to corner but combining this with a 135mm focal length achieves an enormous 9.45^o x 6.30^o field of view @ f2 with a Canon 550D compared with my current set-up of 2.67^ox 1.78^o, opening up whole new imaging possibilities.

Inner rectangle: FOV using William Optics GT81 + focal reducer & ZWO 1600MM-Cool camera
Outer rectangle: FOV using Samyang 135 f/2 & CAnon 550D DSLR camera
It would take approximately a 9 x panel mosaic from the WO to cover the Samyang area!

Furthermore, this much smaller rig is lighter, easier and thus quicker to set-up and break-down. Put together it’s a powerful combination that I hope to fully exploit in the future.

Camera	Equipment	FOV	Resolution
ZWO ASI1600MM-Cool	WO GT81 + 0.80 FR*	2.65^o x 2.00^o	2.05”/px
ZWO ASI1600MM-Cool	Samyang 135 f/2	7.50^o x 5.67^o	5.80”/px
Canon 550D DSLR	WO GT81 + 0/80 FR*	2.67^o x 1.78^o	1.85”/px
Canon 550D DSLR	Samyang 135 f/2	9.45^o x 6.30^o	6.45”/px

*Current set-up

By today’s standards this lens might be considered somewhat old fashioned with no autofocus or image stabilisation etc., but the intrinsic high manufacturing standards and manual focus are excellent for those who know how to handle such a lens and perfect for astrophotography. For such a purpose users generally either create their own rig by adapting various astronomy bits and pieces or use one of a growing number of bespoke brackets that are being made for this increasingly popular lens.

For the moment I chose to use a 3D printed bracket and integrated manual microfocuser, made by the French company AstroKraken and its founder Philippe Leca. Therein the lens is cradled by two hinged rings, which when screwed down hold the lens firmly to either a Vixen bar or Losmandy plate. The microfocuser then fits snuggly around and then clamps onto the focus ring, so that two screws on either side can be adjusted so as to push against a bridge located above and between the two rings, thus providing fine control over the focus ring; the said bridge also has a Synta fitting shoe on top to fix a finder / guide scope. Altogether it’s a neat and very effective design that provides an easy-to-use tailor made platform for the lens, which can then be combined either with a DSLR or mono camera on the back; users of mono cameras tend to recommend changing the lens’ bayonet for a screw fitting and possibly add a third ring for the camera in order to eliminate the possibility of any flexure.

Whilst the AstroKraken bracket works well, the structural layout is inevitably tight making it difficult to view the focus ring settings but once established close to focus, subsequent use of the microfocuser is excellent in finessing the job of focussing before locking down the adjustment screws. In addition, I’ve acquired a second Starlight Express Lodestar X2 autoguiding camera for use with a Skywatcher Evoguide 50ED guidescope but so far have not needed it with short exposures currently being used.

As a project for the new rig I had intended to spend the late summer imaging the suitably large Cygnus HII region but in the end conditions limited my time on this wonderful area of the sky at this time of the year and will have to wait for another time. Notwithstanding, first light using my modded Canon 550D DSLR camera of the said Cygnus area was briefly achieved at the end of July, with promising results (see above – uncropped). More recently, in early September I was able to obtain images of the Veil Nebula (see below – cropped to 70%) and North America Nebula (see top-of-the page, cropped to 80%), in all cases taken at 120sec exposures and ISO 1600. Unfortunately all integration times have been just under 60 minutes for each target and in the long run the real magic of this lens will be unlocked with the addition of a mono camera and much greater imaging times.

Looking back personally and professionally, it’s apparent to me that the concept of the big picture, metaphorically or otherwise, has played a central role in my life and is an area I like to work with; it’s the big picture that provides context, understanding and opportunity. Perhaps it should therefore not be a surprise that in the end my next step in astrophotography will now follow such a path. The detail provided with my current equipment is fulfilling and beautiful but the additional context provided by the Samyang’s extensive FOV can be more insightful and even breathtaking in scope. After something of a slow start, I’m now really looking forwards to spending more time with this new and exciting rig in the future.

Canine Capers

June 1, 2020 by grahamrob in AstroBin, Autoguiding, Deep Sky Objects, Equipment, General Astronomy, Imaging, Narrowband and tagged Bootes, Canes Venatici, M106, M51, M63, Ursa Major | 2 Comments

Following a very poor winter period, spring has been nothing less than spectacular and provided many clear nights for astronomy, ironically made all the better by the covid-19 lockdown. With the near absence of road traffic and especially aircraft – Fairvale Observatory is badly affected by flights from nearby Gatwick, Heathrow and Redhill aerodrome – it has resulted in noticeably better seeing, as well as a quieter and more enjoyable environment overall; it’s worth noting that after experimenting with Deep Sky Stacker (DSS), increasing the Kappa-Sigma clipping parameter from 2.0 to 2.50 for the light subs, in all but the worst cases eliminated aircraft tracks in the final stacked image. Resulting from these favourable conditions, I’ve recently been able to image four otherwise difficult targets, amounting to some 40-hours total integration time, literally unprecedented conditions in the +30 years I’ve lived here.

CanVen Map

Apart from a brief diversion imaging the Leo Triplet, my attention has otherwise been centered on the constellation of Canes Venatici, AKA the Hunting Dogs. At this time of the year the constellation starts to come into view high overhead from the east at about 10 p.m. and crosses the meridian about three hours later. Located below Ursa Major and above Bootes, the relatively small Canes Venatici hosts five Messier objects, four of which are galaxies and it is these I’ve been drawn to. From earlier test shots I determined that the M94 galaxy was unlikely to be suitable for my equipment but I did obtain and have already described images of first M106 and then M63. Notwithstanding, I had unfinished business with the last of the four galaxies, which I therefore now turned to.

In 2019 I was pleased to acquire my first ever image of the wonderful M51Whirlpool Galaxy and its smaller companion, NGC 5195. However, I noted then that the final LRGB image still needed much more integration time than just 2hr 18min. achieved, plus the addition of Ha-subs and that I hoped to return to the Whirlpool and its neighbour as soon as possible for this purpose.

M51 HaLRGBFinal-denoise-denoise

It was therefore a great pleasure to image M51 over no less than seven nights in March and April this spring, which combined with last year’s data resulted in over 16 hours integration time, substantially longer than any previous image I’ve compiled before. Moreover, the quality of seeing also benefitted SNR and guiding quality, thus achieving RMS errors of at least 0.80 arc seconds or better. I did encounter some plate solving issues and had to resort to manual framing on a few nights but fortunately DSS software dealt with alignment OK and the final image is all I could have hoped for (see above + top-of-the-page cropped). Naturally the interaction of the two galaxies is the signature feature of this image but it is the improvement in general colour, detail and addition of Ha-subs highlighting regions of new star formation, that have been most transformative in portraying these objects in all their glory.

Using my current set-up it seems unlikely that the image would benefit significantly from any further data acquisition but I’d like to think I’ll return another day using a larger telescope and higher resolution with which to capture and enjoy even more detail of all these exciting objects of Canes Venatici. It is said that “it’s an ill wind that blows no good” and I am doubtful we’ll ever have such good conditions here again but for now I was delighted to be able to positively exploit this otherwise difficult time in lockdown.

	IMAGING DETAILS
Object	M51 The Whirlpool Galaxy & NGC 5951
Constellation	Canes Venatici
Distance	23 million light-years
Size	11.2’ x 6.9’ 77,000 light-years (M51 only)
Apparent Magnitude	+8.4

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWO x8 ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 13:30:03 DEC 47:11:43 (approx.) Top = South Bottom = North
Exposures	L x 95 R x 62 G x58 B x 66 Ha x 46 = 327 x 180 sec Total Integration Time: 16hr 21 minutes
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	10^th April 2019 +23^rd 24^th 25^th 27^th March & 20^th 21^st 22^nd April 2020@ +22.00h
Weather	Approx. 6^oC RH <=60% 🌙 New Moon approx.

Nice But Dim

March 31, 2020 by grahamrob in Deep Sky Objects, History, Imaging, Nebula and tagged Gemini, Milky Way, Pleiades | 1 Comment

Abell 21 Combo All 2018 2020 RGB FINAL CROP (Large)

Contrary to appearance, a planetary nebula is not a planet but a emission nebula, an expanding shell of glowing ionized gas discharged from a red giant star at the end of its life. At this late stage of stellar evolution the star runs out of fuel to burn, with the result that the outer layers are blown away and expand into space typically in the shape of a ring or bubble. At the centre of the planetary nebula is the remnant of the star, which is left as a White Dwarf.

JEL_ITV_ElementFormation_BG-Plate_Updated_23Oct17

The term “planetary” nebula is therefore completely misleading and derives its name from none other than William Herschel, in an era when such objects were thought to look like planets. We now believe some 10,000 planetary nebulae exist throughout the Milky Way, though only 1,500 have been identified (see NASA HST images below), including M57 the Ring Nebula and M27 the Dumbbell Nebula both popular amongst astrophotographers.

HST PN Such objects are usually short lived and unfortunately small and faint, making them a challenge for smaller telescopes and Bortle 5-6 skies, such as I have at Fairvale Observatory. However, I recently decided to return to the Medusa Nebula, a planetary nebula which I previously had imaged as a test in February 2018. On that occasion the integration time was limited to only 75 minutes (see below), now the objective was to build on the previous data and thereby hopefully improve the image quality.

Abell 21 RGB 2018 Final (Large)

Combining the data from 2018 with that of 2020 resulted in a significant increase in total integration time to just over 5-hours, with the impact on the final image clearly noticeable (see top-of-the-page cropped and below uncropped – showing the difference in alignment between pre-plate solving 2018 & 2020 data), mainly in the form of reduced noise and better colour saturation. I am a little surprised that the improvement was not greater but perhaps it’s a case of either (a) considerably more time is still required, particularly in the weak OIII wavelength, or (b) it’s really too much of a challenge for my equipment?

Ha wavelength

OIII wavelength

However, looking at other images of the Medusa Nebula and considering its size and very low surface brightness, it’s obvious this is one of the more difficult planetary nebula objects to image and all things considered I’m happy with outcome new of this new version.

Abell 21 Combo All 2018 2020 RGB FINAL

	IMAGING DETAILS
Object	The Medusa Nebula AKA Abell-21, Sharpless 2-274 or PK205+14.1
Constellation	Gemini
Distance	1,500 light-years
Size	Approx.. 12’ x 9’
Apparent Magnitude	+15.99

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 px
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 05:55:38 DEC 01:59:40 @20.49h Image rotated 180^o for presentation Top = South
Exposures	37 x 300 sec Ha, 25 x 300 sec RGB Total Time 5hr 10 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5 x 300 sec Darks 20 x 1/4000 sec Bias 10 x Ha & OIII Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	11^th February 2018 + 2^nd & 3^rd March 2020 @ +21.00h
Weather	Approx. 5^oC RH <=75% 🌙 +29% waxing

Reflections 2019

December 21, 2019 by grahamrob in Broadband, Deep Sky Objects, Galaxy, General Astronomy, Imaging, Mosaic, Narrowband, Nebula, Processing, Software, Solar system, Widefield Imaging and tagged Andromeda, Horsehead Nebula, M101, M42 Great Orion Nebula, M51, M74, M78, Milky Way, Wizzard Nebula | Leave a comment

The website Watch This Space (Man) began in 2015 as I started out in astronomy and is a record of my personal journey, comments and thoughts. Apart from the main blog, the website also contains links to other astrophotographers, astronomy tools, astronomy weather, and scientific papers etc., which can be accessed from the top menu.

Whilst there is a photo gallery of my work in this website, an overview of the better images can be found in the My Astrophotography FLICKR album, which can be found in the GALLERY menu. Furthermore, this year I took the plunge and joined the Astrobin community, where my images can be found using the appropriate link also in the GALLERY menu.

Heat Map 2019

During the past year the site was visited from 64 different countries, literally from every corner of the world. I always like to hear from anybody out there – comments, questions, help or just to say hello – and can be contacted via details given in the ABOUT menu section or just leave a comment on any item if you prefer.

Reflections is compiled at the end of each year as a review of my astronomy and astrophotography during the previous twelve months, together with some thoughts on possible future developments.

Overview, Images & Goals for 2020

The past year’s plan was simple: build-on and experiment with developments from the previous year, in particular using Plate Solving to achieve longer integration times and explore further the north sky, which I could now see from the new Shed Observatory and operates during the spring and summer months.

By routinely using Plate Solving integration times, now obtained over a number of nights or even months, have increased by up to four-fold compared to previous years. As a result I concentrated on less objects but for longer time, achieving between 6 to 8 hours of subs on some occasions, the limiting factor as ever being British weather. Although quite modest compared to those able to use fixed observatories, or in clear, dry climates with Bortle 1 or 2 skies, I was very pleased with the positive impact this had on my images.

Starting astronomy and astrophotography somewhat late in the day a few years ago, like many others after retirement, the learning curve was steep and often frustrating. There were times I’ve almost considered giving up but with perseverance I’ve made progress and often get great pleasure from some of the results, as well as just enjoying and learning about this wonderful subject. For me it is just a hobby but recognising some of my achievements and abilities acquired since starting out in 2014, I was especially proud this year to be elected a Fellow of the Royal Astronomical Society. For all the help in reaching this point, I’d like to thank all those who have helped me from the astronomy community, wherever they are.

Favourite Images

My weakness in astrophotography remains processing but having at last obtained some good integration times, this year I made a greater effort to improve these techniques – with some success. Adopting the theme less is more, I imaged just 17 different objects this year – of which nine were full narrow or broadfband images, with the rest being experimental or DSLR – with a total integration time of 65 hours (2018: 25 objects & 43 hours). The resulting images turned out well, achieving Picture of the Week on the British Astronomical Association website on six occasions. It’s therefore difficult to choose favourites from this select group based on merit alone, so this year’s favourites (see below) represent those good images that also mark a significant milestone in my astrophotography. Detailed reviews of these and all other images from 2019 are discussed in dedicated articles that can be found via the Blog Index under the ABOUT dropdown menu.

SHO2 CompF (Large)

Horsehead & Flame Nebula: Usually imaged in LRGB broadband, this narrowband SHO version produced a very different affect and colours, whilst also showing the beauty of the accompanying clouds of interstellar gas and dust. Taken over three nights, at nearly 7-hours, this image was also one of my longest integration times to date.

M101 HaLRGB final Closeup

M101 Pinwheel Galaxy: Given Bortle 5-6 skies, being on the Gatwick Airport flightpath and a using a small refractor, I struggle to image galaxies and often LRGB images in general from Fairvale Observatory. However, on this occasion the combination of 5-hours HaLRGB subs and new processing techniques to enhance the colours, M101 proved the exception and is perhaps my first decent classic spiral galaxy imaged from home. Moreover, the HII regions light up along the spiral arms with the addition of Ha wavelength, producing a dazzling and dynamic image.

Picture saved with settings embedded.

Heart & Soul Nebula: Combining existing data from 2018 of the Heart Nebula and new 2019 data of the Soul Nebula + the intervening space, this is my first albeit modest mosaic, which promises to open up significant possibilities in the future.

RECORD CARD – 2019
Goal	Specifics / Results	Outcome
Improve broadband and narrowband imaging	Achieved major increase of image integration times and overall quality.	MUCH, MUCH BETTER
*Improve processing*	Continuing to make slow improvements, with greater use of new Photoshop techniques.	BETTER
Expand & Improve Widefield Imaging	Despite some good images of the Milky Way in the USA, I never used the Vixen Polarie tracking mount and did not make it to any other dark sky sites = disappointing.	FAILED

My objectives in 2019 mostly went well in (see above), so here goes for 2020:

Imaging: There’s always scope to improve imaging techniques but probably most of all I still need to improve guiding quality and increase exposure and image integration times even further.

Mosaic: Expand the use of mosaic imaging using Plate Solving and new CdC planning software.

Improve processing: I expect this will continue to be something of a challenge for some time to come unless I go to the dark side and adopt software such as PixInsight & / or APP.

New Observatory: Unfortunately this will not be a fixed obsy whilst I continue to live here at Fairvale which is unsuitable. However, I’m hopeful that another location between the Main (North) Observatory and the Shed Observatory might open up the north sky better and by getting away from the high hedges that surround the garden allow longer imaging sessions than can be currently obtained at the Shed.

Other: My mind is always thinking about larger telescopes or a dual rig and / or a new high-end encoded mount but probably not until I make further progress with the above goals and / or move to a better dark sky location – dreaming is part of astrophotography = watch this space!

Although you never know, I don’t see any major breakthroughs in the coming year but more of the same – revisiting familiar objects in order to obtain new image versions based on greater integration time and hopefully using mosaic techniques to build-out images in order to encompass wider areas of the sky. This year I was surprised to discover objects that I had hitherto considered out of reach from my location (M101, M51 etc.), as well as exciting features that were completely new to me and still hold great promise e.g. DWB 111 AKA the Propeller Nebula.

Looking back I’m very happy to say 2019 was an excellent year for astronomy and astrophotography, almost certainly my best yet. You can’t ask for more than that and I hope that WTSM’s Reflections 2020 will record further such success.

Watch this space!

2019 CHRONICLE

Below is a quarter by quarter summary of my astronomy and astrophotography for the year, followed by an imaging record.

JANUARY TO MARCH

Towards the end of 2018 I decided to undertake a project, with the prime objective to gather a much longer period of integration than hitherto achieved by using my newly developed skill of Plate Solving. I’d previously imaged the Horsehead and Flame Nebula in the more traditional colour palette, either with a modded DSLR or by LRGB broadband. However, I’d recently seen this iconic image undertaken using the Hubble Palette to great affect and was inspired to do the same myself. Thereafter, for more than 2-months the clouds rolled in and I thought my project would then be impossible, not least because by now Orion had crossed the Meridian in the early evening and imaging times were at best limited. But as is often the case with astrophotography everything suddenly changed and it was game on!

The first evening of clear skies since 11^th November 2018 coincided with the full lunar eclipse on 21^st January, which I was therefore able to image once again. Then six days later a very untypical clear and quite warm period of weather arrived and I was able to complete my intended project after all, with further time to image both the Great Orion Nebula and the reflection nebula M78 + Barnard’s Loop (see images below).

HaLRGB2FINALcrop (Large)

Combined +180 degrees 3+5min HaLRGB (Large)

Achieving much longer integration times of between 5 and nearly 8-hours, the impact on the resulting images was transformative. I was especially pleased with the outcome of the Horsehead project in SHO (see Favourites Images section) but found the Ha-only starless version of the same scene (see below) particularly mesmerising, as the large HII structures throughout this region bring the image to life.

NGC 2024 Ha Starless2

By the end of February the night sky at 51^o latitude has moved inexorably on to the so-called Galaxy Season, which provides something of a dearth of imaging opportunities for my 81mm telescope. However, with a good patch of weather at the end of March, whilst experimenting with the Leo Group I noticed that small areas of Ursa Major region could be seen directly above for a couple of hours, which to my surprise opened up a whole new world of possibilities hitherto considered unavailable. Shortly after I managed to obtain almost 5-hours of data on M101 the Pinwheel Galaxy, which is one of my best galaxy images taken from Fairvale Observatory (see Favourite Images section).

APRIL TO JUNE

Having discovered the albeit limited possibilities of seeing Ursa Major, I moved to the Shed Observatory early in April, which by then afforded slightly better views of the same area of sky and thereby to my great joy provided the possibility of imaging the wonderful Whirlpool Galaxy, M51. Unfortunately time was somewhat limited but it was better than nothing and I was thrilled to obtain an image of this wonderful object for the first time. Weather permitting I’ll be back for more data in 2020 with which to build on the promising result obtained this year.

LRGB Image FINALX2 (Large)

By the end of April just 8-weeks away from the summer solstice astronomical darkness is in short supply. Fortunately having moved earlier to the Shed Observatory this year, I was in a good position to return to inaging the Bodes and Cigar Galaxies (see below), which had been my first ever image of north sky objects in 2018.

LRGBFinal (Large)

JULY TO SEPTEMBER

From May until late July the absence of Astronomical darkness makes astronomy difficult and frankly having progressed from the time of being a beginner, it is quite refreshing to take a break. Therefore it was only after an evening viewing the partial eclipse on 16^th July and a brief experiment with the Wizzard Nebula (something for the future) at the beginning of August, that much later I returned to astrophotography seriously.

SHO2SCcrop (Large)

Having messed up imaging the Soul Nebula with poor framing in 2018 and being at the Shed Observatory, I decided to re-image the Soul properly, together with some of the adjacent sky in order to combine the new data with last year’s adjacent Heart Nebula to form a mosaic of both objects. I don’t know why but this was my first attempt at a mosaic. Only very recently has integrated software for mosaic planning combining Cartes de Ciel and Astrophotography Tool for image capture has been released. However, on this occasion I planned and implemented the said mosaic imaging manually, with a satisfying outcome (see Favourite Images section) but with the new software now available I hope to embark on more extensive mosaic projects in the near future.

This year’s astrophotography has followed two themes, the aforementioned ‘less is more’ with the aim of producing better images using much greater integration times. The second has been largely determined by chance, being the discovery of new objects that had hitherto either been unknown to me or considered to be out of view from Fairvale Observatory; the combination of my house, very high hedges + trees and adjacent houses obscures large swathes of the night sky. Earlier in the year such chance had led me to the M101 and M51 galaxies and in the autumn it was first the iconic Pacman Nebula and then an exciting area of Cygnus constellation.

Pacman is not particularly large for my equipment but nevertheless produced a decent narrowband image, my last from the Shed Observatory for this year. Not until late September did the clouds again relent for my next project that initially seemed something of a long shot but actually turned out very well. The Propeller Nebula is located in a vast HII region of the Cygnus Constellation, which from my point-of-view was a complete surprise. At some 25 arc seconds the nebula is again on the small side for my equipment but the complexity of the adjacent HII region transforms the wider image into something really spectacular (SHO version below), which I certainly intend to visit again next year to build on the current data and explore further afield the HII region which presents exciting possibilities.

SHO F HLVG (Large)

A subsequent long trip to the USA stopped all astronomy in Surrey but a couple of evenings out in Wyoming and Utah produced some incredible dark skies and DSLR Milky Way images (see below). Despite the remoteness of Spilt Mountain in the UTAH section of the Dinosaur National Monument – designated a Dark Sky Area – whilst imaging at 20 second exposures only one-in-ten images were without a plane track, very sad.

IMG_2345 ComboX

OCTOBER TO DECEMBER

Prior to the arrival of Orion and other fun objects of the mid-winter night skies, imaging opportunities are sparse with my equipment but it’s been a couple of years since I last imaged M31 the Andromeda Galaxy and therefore for two evenings in late October it was time to give our neighbour the extended integration treatment. At 7½ hours data acquisition went well but although the processed image is probably my best yet of this object, there’s room for improvement, which I suspect will require a move to more advanced processing software?

HaLRGBx5b (Large)

ASTROMINAGING RECORD 2019

No	Date	Type	Object	Name

1	21/01/19	DSLR	Full Lunar Eclipse

2	27/01/19*	NB	Barnard-33 & NGC 2024	Horsehead & Flame Nebula

3	23/02/19*	Combo	M42	Great Orion Nebula

4	25/02/19*	Combo	M78	Reflection Nebula Orion

5	12/03/19	BB	NGC443/444	Jellyfish Nebula

6	24/03/19	Combo	M95/96/105	Leo-1 Group

7	29/03/19*	Combo	M101	Pinwheel Galaxy

8	10/04/19	Combo	M51	Whirlpool Galaxy

9	13/04/19	BB	M81 & m82	Bodes & Cigar Galaxies

10	16/07/19	DSLR	Partial Lunar Eclipse

11	02/08/19	NB	NGC 7380	Wizzard Nebula

12	23/08/19*	BB	IC 1848	Soul Nebula + Mosaic Link

13	26/08/19	NB	NGC 281	PacMan Nebula

14	05/09/19*	NB	DWB 111	Propeller Nebula

15	Sept	DSLR	Milky Way	Split Mountain Utah

16	22/10/19*	Combo	M31	Andromeda Galaxy

17	18/11/19	BB	M74	Galaxy

18	18/11/18	NB	SH2-240	Spaghetti Nebula

*multiple evenings Combo = HaLRGB Underlined = BAA published

POSTSCRIPT

The ones that got away – imaged but not seen in WTSM this year – warts and all

RHB_2ajelly (Medium)

I saw some wonderful narrowband versions of the supernova remnant IC 443 Jellyfish Nebula this year, in particular adopting a wider view to incoporate its sentinel-like parner stars Tejat (Mu Geminorum) left and the tripple star Propus (Eta Geminorum) right, together with the reflection nebula IC 444 in the background. As an experiment I think it may hold promise but will require a lot more integration time to improve the quality, colour and bring out more of IC 444.

M95_96_105 (Medium)

I’ve tried the Leo-1 group (M95/96/105) before but, as they say, if you don’t succeed try again. Unfortunately the passage of time didn’t help – I need a larger telescope to do these critters justice!

IMG_2336 (Large)

Dinosaur National Monument – Split Mountain, Utah. Even at this wonderfully remote location, which is one of the darkest places in the USA, passing planes still get in the way of a good image – just like at Fairvale Observatory!

M74 LRGBx (Medium)

At <=10 arc minutes the spiral galaxy M74 is too much for my equipment.

SH2-240 AB combined Ha Stretch (Large)

Located between the constellations Auriga and Gemini, SH2-240, Simeis 147 AKA the Spaghetti Nebula is a very large (+3 degrees) supernova remnant but it’s very low brightness makes imaging extremely difficult. In fact prior to and during capture in Ha-wavelength, I had no idea if it was even within the image frame. Aggressive stretching shows that it was there but only much darker skies and probably longer exposure time is likely to produce a more viable picture.

Other Worlds

June 10, 2019 by grahamrob in Broadband, Galaxy, History, Imaging and tagged Canes Venatici, Ursa Major, Whirlpool Galaxy | 1 Comment

LRGB Image FINALX2 (Large)

Being galaxy season it was appropriate that the BAA spring meeting this year on 27^th April was all about – galaxies. This was my first BAA meeting and I’m pleased to say it was well attended and very worthwhile, I especially enjoyed the following presentations:

Prof. Richard Ellis: The Quest for “Cosmic Dawn”;
Prof. Chris Impey: Einstein’s Monsters: Black Holes at the Heart of Galaxies;
Stewart Moore: Galaxies: A Brief History of Discovery, and
Owen Brazell: Observing Galaxy Clusters.

It seems incredible that just 100-years ago the prevailing view was that Universe consisted entirely of the Milky Way, though that was soon about to change. Whilst Immanuel Kant had proposed the possibility of galaxies outside our own as long ago as 1755, it was not until Edwin Hubble’s work at the Mount Wilson Observatory, California that the existence of other worlds, in the form of galaxies, was proven and accepted during the period between 1924 and 1929.

Following Copernicus’s controversial theory in 1543 that the Earth orbited the Sun, the evidence this time that there was much, much more beyond the Milky Way was equally profound in its implications, if not more so. However, I was surprised to learn that it was Vesto Slipher and not Hubble who discovered the redshift of galaxies that was fundamental to understanding that galaxies existed outside the Milky Way that were moving away from us – it would seem to me that he deserves much greater credit as well as Hubble for this work. The current estimate is that there are some 100 to 200 billion galaxies in the observable universe but new research now estimates that the total number is likely to be at least ten times greater! Either way there are many other worlds out there.

After recently learning that I could after all see and image a few larger galaxies from Fairvale Observatory in-and-around the Ursa Major constellation, it was to my great delight when I then discovered that one of them was M51 AKA the Whirlpool Galaxy. I’ve seen many images of this wonderful object and was frustrated that it seemed to be completely out of sight from here but thankfully that is not the case. Armed with this knowledge, following an imaging session of M101 at the end of March, I therefore went on and immediately grabbed a single Luminance test sub of M51 (below) before it disappeared behind the roof of my house, (a) because I could, and (b) to see how it looked with my equipment. The answer was that it was almost certainly a viable target for another night when more time was available.

M51 KStar

While located just above the star Alkaid in Ursa Major, M51 is now included within the nearby constellation Canes Venatici; created by Johannes Hevelius in the 17^th Century, M51 was previously in Ursa Major. One of the more famous grand-design spiral galaxies i.e. with prominent well-defined spiral arms, the Whirlpool Galaxy forms a striking image as it interacts and distorts the dwarf galaxy NGC 5195 located at the tail of its outer second arm. The exquisite structure of M51 is further enhanced by large star-forming regions along the spirals, which are picked out by the associated hydrogen alpha gases.

Timing is everything: M51 is in a tricky position seen from Fairvale Observatory, obscured for much of the time at the north viewing location by the house and from the south location by a 20ft hedge – in between there’s a maximum window of no more than 2.5 hours for imaging!

The smaller dimensions of the M51 galaxy would normally place it at the limit of my equipment for imaging but is helped by its aforementioned clear-cut features, strong colours, favourable apparent magnitude and its location towards the zenith immediately above my observatory. This has long been in my top-10 ‘must-do’ imaging list but hitherto was thought to be out of view. Unlike M101, which lies below Alkaid i.e. south, being further north the imaging time of M51 from Fairvale Observatory North is even shorter before it too retreats behind the rooftop. However, this year I decided to move early to the summer location at the bottom of the garden – Fairvale Observatory South – where it was possible to gain a slightly longer view, though still only just over two hours before it disappears for the night, this time behind the adjacent 20-foot hedge!

It’s clear that the final LRGB image would be greatly enhanced with further integration time and the addition of Ha-wavelength but for now I’m content that at last I’ve managed to capture this spectacular object on camera. Skies permitting I hope to return to the Whirlpool and its companion NGC 5195 as soon as possible.

	IMAGING DETAILS
Object	M51 The Whirlpool Galaxy & NGC 5951
Constellation	Canes Venatici
Distance	23 million light-years
Size	11.2’ x 6.9’ or 43,000 light-years (M51 only)
Apparent Magnitude	+8.4

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWO x8 ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 13:30:03 DEC 47:11:43 Top = South Bottom = North
Exposures	(A) L 18 x 180 sec RG 9×180 sec B 10 x 180 (Total time: 2hr 18 minutes)
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	10^th April 2019 @ +22.00h
Weather	Approx. 6^oC RH 60% 🌙 ¼ waxing

Fireworks

May 23, 2019 by grahamrob in Broadband, Deep Sky Objects, Galaxy, General Astronomy, Imaging and tagged M101, Pinwheel Galaxy, Ursa Major | 2 Comments

HaLRGB final-denoise2-denoise-PS (Large)

At Fairvale Observatory North it’s normal that I struggle to find suitable objects when the so-called Galaxy Season arrives in late winter through spring. Despite the abundance of galaxies my William Optics 81mm aperture rules out all but a few for imaging as they are mostly just too small. However, smaller galaxies that make up features such as Markarian’s Chain and the Leo group do produce a pleasing widefield image full of the so-called faint-fuzzies but hitherto with the exception of M31 the Andromeda galaxy I’ve struggled to obtain the real thing – a decent, full-on spiral galaxy – they are there of course but are either obscured to the north by my house and trees or, as indicated, are too small for my equipment to resolve properly.

M95_96 Anotated

Nonetheless, this year after playing around imaging the aforesaid Leo Group (see above), I looked directly above the observatory and to my surprise discovered a new world of galaxies close to the Zenith that were just visible, briefly transiting along the southern edge of the house roof, which included a few large classics in-and-around the constellation Ursa Major. After 2-hours imaging the Leo group time was too short for a serious attempt at any of these galaxies but nonetheless was sufficient to experiment with what looked like a potential target, the wonderful M101 the Pinwheel Galaxy, which at over 28 arc seconds showed real potential with only 42 minutes of subs before it disappeared out of sight for the night. Moreover, large parts of Ursa Major and nearby galaxies also briefly appeared at other times on the night from behind the roof, tracking close to the gutter for nearly 2.5 hours before returning behind the roof in a similar manner to M101. Thus assuming full set-up could be achieved earlier in the evening, this seemed to provide a window of opportunity that I grasped over two subsequent evenings with a very satisfactory outcome.

With nearly 5-hours of subs, processing of M101 would be a challenge in order to bring out the galaxy’s colours and perhaps highlight the stellar nursery areas that are found along the spiral arms and are rich in Ha-light. To do this I first changed the RGB image stack to Lab Colour in Photoshop, increased the saturation in the (a) and (b) channels before returning to RGB mode. This had the desired effect of successfully enhancing the colours, which can otherwise look washed-out after stacking, stretching and combining. After this I split the RGB channels and pasted the Ha-stack into the Red channel, before re-combining again into an RGB image, at which point the H II regions along the spiral arms just lit up! These were both new processing techniques for me that greatly improved the final image and hold great promise for processing HaLRGB objects in the future.

M101 closeup data crop

M101 widefield data crop

The final image (top of the page + crop below) far exceeded my expectations in detail and colour, showing off much of the galaxy’s wonderful structure and the aforementioned HII regions. There’s no doubt that further integration time will benefit the faint extremities of the galaxy but for now it was a very satisfying outcome of a spectacular object that hitherto I thought was beyond my seeing at Fairvale Observatory. Also noteworthy, the image has caught a plethora of companion galaxies close to and around M101 (see annotated images above), most conspicuous of which is the classic side-view of NGC 5422 (left of M101) and the more unusual dwarf spiral galaxy NGC 5474 (right of M101), which has been noticeably distorted by gravitational interaction with the Pinwheel itself. All-in-all a fine display of galactic fireworks worthy of November 5^th.

M101 HaLRGB crop-denoise-denoisePS

	IMAGING DETAILS
Object	M101 Pinwheel galaxy
Constellation	Ursa Major
Distance	20.9 million light-years
Size	28.8’ x 26.9’ or 170,000 light-years
Apparent Magnitude	+7.86

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 14:03:15 DEC 54:20:46 Top = North
Exposures	(A) L 31 x 180 sec HaRGB each 16×180 sec (Total time:4hr 45 minutes)
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec & 15 x 60 sec Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	29^th & 31^st March 2019 @ +22.00h
Weather	Approx. 8^oC RH <=70% 🌙 ¼ waning

Hunting Orion

May 3, 2019 by grahamrob in Broadband, Deep Sky Objects, General Astronomy, History, Imaging, Nebula and tagged Orion | Leave a comment

Combined +180 degrees 3+5min HaLRGB (Large)

In Greek mythology it is said that Zeus, the god of thunder, placed a giant huntsman amongst the stars as the constellation Orion. Today it is one of the most recognizable of the 88 constellations in the night sky and certainly one of the most popular amongst astronomers. Towards its extremities it is defined by the red supergiant star Betelgeuse at the top-left and the massive blue supergiant Rigel lower-right, divided in the centre by Orion’s so-called ‘belt’ formed by the line of bright stars from left-to-right: Alnitak, Alnilam and Mintaka. These and the other stars that make up the constellation of Orion are of great interest to astronomers and also make an attractive widefield image with a standard camera. But the more serious astrophotographer is mainly interested in the panoply of exciting DSOs that lie within and around Orion that I have therefore been pursuing myself since late January.

My quarry started with the Horsehead and Flame nebulae imaged in narrowband processed using the Hubble Palette technique in SHO to great effect. Much to my surprise a spectacular period of warm weather and clear skies four weeks later then allowed me to capture the Great Orion Nebula over three nights in HaLRGB with an equally good result. Such was the fine weather conditions that I was then able to continue over a further two nights – five consecutive nights of imaging in the UK in late February, unprecedented in my experience – with the objective now being the reflection nebula M78.

M78 is the brightest diffuse reflection nebula of a group that belongs to the Orion B molecular cloud complex but with an apparent size of 8 x 6 arc seconds it is a something of a challenging target with my equipment. Notwithstanding, with the mono CMOS ZWO camera and the opportunity of obtaining increased integration times I considered it worth a try and was not disappointed with the outcome.

I generally like to present images in their natural orientation but this time I’ve chosen to rotate the it 90^o anticlockwise, thus allowing the wider horizontal framing to better show M78 and the dramatic red Ha-light of nearby Barnard’s Loop together. As with M42 previously, I first stacked and processed two exposure sets, short 60 second and long 300 second subs, before then combining them so as to tease out subtleties within the reflection nebula itself and provide greater control of the otherwise dominant Barnard’s Loop. Despite my concerns about equipment and scale, I’m very pleased with the outcome of the main image (top-of-the-page), which beautifully shows off both the aforementioned objects to great effect and has even extracted some of the colour and detail of associated star clusters within and around the nebula. Not surprisingly the cropped version of M78 itself starts to look a little noisy but is nonetheless interesting (below).

Combined crop 3+5min HaLRGB (Large)

After a very unpromising few months, the weather, Orion and my astroimaging took a surprising turn for the better from the end of January. As a result of much longer integration times using plate solving over multiple sessions, combined with varied exposure times and more complex processing, I successfully managed to bag three classic deep sky objects of the Orion constellation – what’s not to like?

	IMAGING DETAILS
Object	M78 Orion reflection nebula
Constellation	Orion
Distance	1,350 light-years
Size	8’ x 6’
Apparent Magnitude	+8.3

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 05:47:37 DEC 00:20:59 Top Left = North Bottom Left = East
Exposures	(A) LRGB 8 x 180 sec Ha 10 x 180sec (Total time: 1hr 24 min.) (B) HaLRG 12 x 300 sec B 17 x300 sec (Total time: 5hr 25 min.)
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec & 5 x 300 sec Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	25^th 26^th 27^th February 2019 @ +19.45h
Weather	Approx. 8^oC RH 60 to 80% 🌙 ½ waning

Eleventh Hour

April 16, 2019 by grahamrob in Broadband, Deep Sky Objects, General Astronomy, Imaging and tagged Orion | Leave a comment

HaLRGB2FINALcrop (Large)

As outlined in my last post Horseplay, it seemed like plans for imaging over the winter were going to be completely scuppered this year, with weeks of cloud cover from mid-November through to late January. I was therefore very grateful for three clear nights at the end of January that finally enabled me to carry out my principal winter imaging project of the Horsehead and Flame nebulae in narrowband. Notwithstanding, given the preceding bad weather and the onset of galaxy season, I reckoned that this was likely to be the end of my imaging for a while, which could not have been further from the truth as more than two months of good night skies (on-and-off) then followed.

Although by late February Orion is crossing the Meridian early in the evening, darkness is still prevalent at the same time and with the aforementioned good conditions it’s been a bonus to catch more of Orion’s objects before they finally disappear for the year. I’ve successfully imaged some parts of Orion before with the ZWO1600MM-Cool camera but for various reasons they’ve mostly been short integration times in narrowband. It was therefore obvious that given this unexpected opportunity, on this occasion I should attempt to image everyone’s astrophotography favourite – M42 the Orion Nebula in LRGB.

At some 1,500 light years distance, M42 is the closest large star forming nebula to Earth and always holds great promise when imaging. I’d previously obtained some good images of the Orion Nebula with a modded-DSLR camera and more recently a few narrowband images in 2017 showed the promise of using the new ZWO CMOS mono camera. Now with unusually good weather I wanted to try and achieve an image that really showed off M42 and its neighbours M43 and the Running Man Nebula (SH-279) in all their glory, paying particular attention to the more difficult inner structures and associated Ha nebulosity. In order to achieve this I first imaged in HaLRGB at 180 sec exposures with Unity settings for 5½ hours and then at shorter 60 sec exposures for 1 hour over three consecutive nights.

Luminosity @ 180sec

Luminosity @ 60 sec

With much longer integration times than before, careful processing and manipulation to bring the long and short exposure images together, I’m very happy with the final result, which I believe achieves most of the aforementioned objectives. Internal structure and colour is shown to good effect but I’m especially pleased with the addition of the Ha data, which dramatically enhances those areas where present together with interstellar dust within and around the main objects; I’m already planning to add more Ha data next year to further intensify the aforesaid impact.

M42 Ha data

Obtaining such results at this late stage of February was completely unexpected and, I thought, would effectively mark the eleventh hour this year for Orion and the rich collection of other DSOs that are found across the winter sky. But no, there was much more to come – watch this space!

	IMAGING DETAILS
Object	M42 Orion Nebula + M43 & Running Man Nebula (SH2-279) etc.
Constellation	Orion
Distance	1,500 light-years
Size	65’ x 60’ or 24 light-years (M42 only)
Apparent Magnitude	+4.0

Scope	William Optics GT81 + 0.80 x Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 05:35:09 DEC -05:08:31 Top Right = North Top = North East Bottom Left = South Bottom = South West
Exposures	(A) L 20 x 180 sec R 24×180 sec G 25 x 180 B 24 x 180sec Ha 17 x 180sec (Total time: 5hr 30 minutes) (B) 12 x 60 sec HaLRGB (Total time: 1hr)
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec & 15 x 60 sec Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	23^rd 24^th 25^th February August 2019 @ +19.40h
Weather	Approx. 7^oC RH <=75% 🌙 ¾ to ½ waning

Horseplay

February 22, 2019 by grahamrob in AstroBin, Deep Sky Objects, Imaging, Narrowband, Nebula, Processing and tagged Flame Nebula, Horsehead Nebula, Orion | 2 Comments

SHO2 CompF (Large)

Who doesn’t like Orion and its constituent parts – M42/43, M78, the Witch’s Head, Barnard’s Loop etc.? For many its annual appearance in the night sky is greatly anticipated and will form one of the main astrophotography highlights of the year as it passes across the sky between late November and February. For me a basic afocal image of the Great Orion Nebula for the first time in 2013 marked something of an epiphany, as it demonstrated the power of long exposures in capturing the otherwise hidden beauty and excitement of Deep Sky Objects.

Since taking up astronomy and then astrophotography, I always return to at least one of Orion’s objects each year, initially to see if I could just capture it on camera with my equipment and then to try and improve the image of each target. It’s been a gradual process but I’m pleased to say I’ve usually managed to achieve such improvements over time, which has been both satisfying and often exciting – such is the nature of these objects. Progress almost always resulted from one or more of four developments: new equipment, new software, new techniques and better processing.

Each step was usually small but occasionally a quantum change took place, such has been the case during the past two years: first with the change from DSLR to a CMOS mono camera and then, more recently, learning to plate solve. I was reluctant to change to a traditional CCD mono camera which usually requires very long exposures that, in my opinion, is incompatible with British weather, light pollution and the frequent overhead passage of aircraft where I live between Gatwick and Heathrow airports – if one doesn’t get me the other will, or the low flying helicopters that pass over my observatory throughout the night from nearby Redhill aerodrome!

It was therefore very fortunate that at the same time I wanted to upgrade my camera from a DSLR, the new CMOS sensor technology had literally just arrived on the market. With low read noise and shorter exposures, the ZWO1600MM-Cool mono camera I purchased has been a revolution for me, as well as the entire astroimaging community. Furthermore, the use of narrowband imaging has added a completely new dimension to my astrophotography – apart from the ability to image when the Moon’s about each month and defy light pollution, narrow Ha-OIII-SII wavelengths reveal a whole new world that is both interesting and often dramatic in appearance.

Notwithstanding these developments, I was hitherto hampered by limited integration times of just over two hours (at most) either east or west of the Meridian, until in 2018 I finally mastered (probably that’s overstating my current prowess) plate solving, thereby making integration times literally infinite. All I needed now was clear skies! Despite my enthusiasm for astrophotography, there have been times over recent months when I’ve questioned my choice of hobby and even maybe giving up. Given sufficient funds it is possible to have the most incredible imaging set-up, capable of obtaining equally incredible images – subject to user ability – but if the sky remains cloudy it’s no more than a pile of expensive junk!

Having obtained a very decent LRGB image of the Pleiades on 17^th November, armed with the ZWO1600 camera and my new plate solving skills, I decided to take on a project over the winter months. My objective was to obtain one very good image based on a much longer integration time than I’ve previously achieved, acquired by imaging the same object over as many nights as possible during December and January. However, as Robert Burns once put it “The best laid schemes o’ Mice an’ Men, / Gang aft agley,” (translated – the best laid plans of mice and men often go awry). Apart from one evening that fortuitously coincided with the lunar eclipse on 21^st January, the skies here remained obscured by cloud from November 18^th until January 27^th (or 70-days!!!) and I thought my project was scuppered, that is until the other qualities required of astronomy came into play: patience and good luck.

My first image of the Horsehead & Flame Nebulae, 23rd November 2014: William Optics GT81 +FF, Canon 700D (unmodded), SW AZ-EQ6 GT mount, 30 x 90 secs @ ISO1600 + full calibration

The Horsehead and Flame nebulae are traditionally imaged in LRGB colour, indeed my first and subsequent images of these objects have been mostly undertaken in this way (see image above). However, inspired by a narrowband image of these objects I’d seen earlier last year, I too wanted to try and capture these nocturnal bedfellows in narrowband and process the subs using the Hubble Palette technique. Given the aforementioned cloud problem, by the time late January had been reached Orion was already slipping over the western horizon for another year and I thought the project was dead before it could even start, at which point good luck played its part. Starting on 27^th January and for three out of the four evenings, the sky cleared and I eagerly launched into the long awaited project.

Unfortunately by now Orion crossed the Meridian about 9 p.m. and most imaging could only be undertaken on the west side, thus limiting each night’s subs again to 2½ hours or less. But with three nights in the bag before inevitably the cloud returned on the 31^st January, I had secured 106 x 5-minute Ha, OIII and SII subs or 6 hours 50 minutes of total integration time, at least three times what I had ever previously achieved. The key was plate solving, as each night I could return to exactly the same part of the sky and continue imaging the same objects to the nearest pixel. Having obtained and reviewed the data, it was now time to start processing.

NGC 2024 Ha Starless2

Given the quality and quantity of data obtained I decided to take my time processing and, furthermore, try to use some new techniques to make the very best of the final image. I was particularly keen to tame some of the brighter stars like the blue supergiant Alnitak located uncomfortably close to the Flame and at the same time bring out the interstellar dust that is present in the foreground below the Horsehead and across the lower right quadrant, which becomes evident in the starless processed Ha layer (see image above). It took quite a while but in the end I am very pleased with the outcome, which I think shows all the benefits of longer data integration and the extra care taken processing. The final SHO narrowband version of the Horsehead and Flame nebulae looks a real cracker, perhaps one of my best and has been worth all the patience and additional time taken to show these two objects and the adjacent region literally in a new light.

Needless to say, I’m already thinking about next year, cloud permitting! I hope to return to the Horsehead and Flame for another playtime next winter, in order to acquire more subs with which to build further on the foundation achieved this year by a stroke of luck at the very end of Orion’s annual visit – can’t wait.

	IMAGING DETAILS
Object	(i)Horsehead Nebula (Barnard 33) & (ii) Flame Nebula (NGC 2024)
Constellation	Orion
Distance	1,500 light-years
Size	(i)8” x 6” & (ii) 30’ x 30’
Apparent Magnitude	+10.0

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQ-ASCOM computer control
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera	ZWO1600MM-Cool (mono) CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PS2, Deep Sky Stacker & Photoshop CS2, HLVG
Image Location & Orientation	Centre RA 05:40:57 DEC -02:30:55 Top = North
Exposures	40×300 sec Ha+34×300 sec OIII+32x300sec SII (Total time: 6hr 50min )
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5×300 sec Darks 20×1/4000 sec Bias 10xFlats Ha-OIII-SII @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	27^th, 28^th & 30^th January 2019 @ +21.30h
Weather	Approx. <=1^oC RH <=90% 🌙 ½ to ¼ waning