It’s all about the wavelength

For the moment, putting aside the duality of light as a wave-particle (quantum) form, the behaviour of light in the visible spectrum can be both fascinating and a problem for the astronomer.  As my tracking has improved (and hopefully will get even better) it has been possible to increase exposure times from a maximum of 40 seconds (and that was pushing it), to comfortably 90 seconds and sometimes more.  The impact is that more light is gathered by the camera’s sensor and the outcome is greater detail and more colours – this all helps, a lot, when the light may travel for thousands or even millions of light years before hitting the sensor.

Unfortunately Fairvale Observatory is located on the southern edge of London and about 8 miles north of Gatwick airport, the result is that all that lovely light that has travelled from distant objects in the Universe has to compete with man-made light pollution.  Last week I therefore invested in an Astronomik CLS filter http://www.astronomik.com/en/, which clips inside the camera, just behind the lens, and blocks the spectral lines of mercury and sodium-vapour lamps, letting the remaining part of the visible spectrum and H-alpha through.

  • The horizontal axisis the Wavelength in Nanometers (nm). 400nm is deep blue, at 520nm the human eye senses green and at 600nm red. At 656nm is the famous “H-Alpha” emission line of hydrogen.
  • The transmission in %is plotted on the vertical axis.
  • The redline shows the transmission of the filter.
  • Visual filters: The greyline in the background shows the relative sensitivity of the human eye at night. The maximum is at ~510nm and drops to longer and shorter wavelengths. You can easily see, that you can´t see anything of the H-alpha line at night (even if you can during daylight!) The sensitivity at 656nm is 0% at night!
  • Photographic filters: The grey line in the background shows the sensitivity of a typical CCD sensor.
  • The most important artificial emissionlines are shown in orange. The artificial light pollution is dominated by see mercury (Hg) and sodium (Na), which are used in nearly all streetlights.
  • The most important emission lines from nebulasare shown in green. The most important lines are from ionized Hydrogen (H-alpha and H-beta) and double ionized oxygen (OIII).

The major emission lines of artificial light pollution:
| Hg 435,8nm | Hg 546,1nm | Hg 577,0nm | Hg 578,1nm |
| Na 589,0nm | Na 589,6nm | Na 615,4nm | Na 616,1nm |

The major emission lines of nebulas:
H-β 486,1nm | OIII 495,9nm | OIII 500,7nm | H-α 656,3nm

Since my recent success imaging the Orion Nebula I’ve been frustrated by bad weather, cloudy skies and a full Moon.  With a brief gap in the clouds last night I therefore couldn’t resist the opportunity to try out the new filter with the camera but without using the telescope.  Shooting two sets of pictures, with and without the filter, and using a telephoto and 50 mm standard lens, the results were both successful and perplexing.

As expected it darkens the sky, a lot, but also skews the resulting image towards blue which subsequently has to be adjusted during processing, complicating the question of what is the right colour even more.  It is a known fact that despite the obviously very large distances of astrophotography subjects, some camera lenses need to be focussed just short of the lens‘s infinity position.  However, with the standard lens the focus point was very different when using the filter, noticeably less than without the filter.  This seems quite strange and I have not quite worked out why this should be so, except the loss of and therefore change in wavelength of the light?

It will be interesting to see how the filter works when imaging deep sky objects using the telescope once the weather clears but the preliminary tests are promising.  Certainly the ‘loss’ of light incurred will require longer exposures so I had better sort out autoguiding soon, my next challenge.

Without CLS filter, 8 secs @ ISO 800

Without CLS filter, 8 secs @ ISO 800

With CLS filter,  8 secs @ ISO 800

With CLS filter, 8 secs @ ISO 800

Milky Way - in the Tarazed region -  60 seconds (only!) @ ISO 800

Milky Way (Tarazed region) without CLS filter                        60 seconds (only!) @ ISO 800

Veil Nebula, with CLS filter, 90 secs @ ISO 800 (+ plane trace!) - unprocessed

Veil Nebula (and aircraft trace!) with CLS filter              90 secs @ ISO 800  – unprocessed

Veil Nebula Canon 700D + 50mm lens, with tracking, unguided & processed 15 x 90 secs @ ISO 800

Veil Nebula
Canon 700D + 50mm lens with CLS filter, tracking, unguided & processed 15 x 90 secs @ ISO 800

Gotcha!

Two of astronomy’s most iconic images are Saturn and the Orion Nebula, M42 – one a highly distinctive planet of our Solar System, the other a trade mark of the winter sky as part of the Orion Constellation.  Both therefore seem quite familiar but still need to be seen or better still captured on camera to personally experience their magic.

The Orion Nebula or Great Orion Nebula, is a diffuse nebula located just south of Orion’s belt in the constellation of Orion.  It is approximately 1,344 light-years from earth and 24 light-years in diameter, which with an apparent magnitude of +4.0 is visible from Earth.  Studies of the nebula have revealed much about how new stars and planetary systems are formed, indeed it is considered a stellar nursery for new ‘baby’ stars, typically only a few hundred thousand years old.  Some 700 stars have been identified as formed from this nebula, most notably the ‘Trapezium’ asterism in the centre of the nebula, consisting of six bright stars. Spectacular red colours arise from hot hydrogen gas, whilst dust reflects the blue light from hot blue stars within the nebula.

The Orion Constellation from Fairvale Observatory last year  - the Orion Nebula is just below the three central stars (Orion's belt) in the centre of the three lower stars

The Orion Constellation from Fairvale Observatory last year – the Orion Nebula is just below the three central stars (Orion’s belt) in the centre of the three lower stars (Orion’s sword)

Due to its sheer beauty and notoriety I have previously dabbled with attempts to image the Orion Nebula before, initially by compact camera and subsequently by DSLR on the Skywatcher 150PL telescope, with limited success.  Notwithstanding, the colours of the nebula were evident and even four of the main stars of the Trapezium could be seen – at the time I was quite pleased but equally frustrated as I was unable to capture this magnificent object at its best.

Afocal image of the Orion Nebula in 2013: I was pleased at the time with the colour is showed and even the Trapazium stars

Afocal image of the Orion Nebula in 2013: I was pleased at the time with the colour it showed and even the Trapezium stars

Orion Nebula later in 2013: DSLR & Skywatcher 150PL, single photograph, shows better colour and detail of the Trapezium

Orion Nebula later in 2013: DSLR & Skywatcher 150PL, single photograph, shows better colour and detail of the Trapezium

One year on, new equipment, new skills and a dark sky and all that has changed.  Very early on last Sunday morning I succeeded in imaging the Orion Nebula in all its glory, in what must be my very best astro photograph to date. Gotcha!

The Orion Nebula October 2014 - the secondary feature in the top left corner is another nebula, M43.  Orientated with equatorial North up and East to the left. Canon 700D unguided | 20 x 90 secs + darks/bias/flats @ ISO 800

The Orion Nebula October 2014 – the secondary feature in the top left corner is another nebula, M43.   Orientated with equatorial North up and East to the left.
WO GT 81 Canon 700D  + FF unguided | 20 x 90 secs + darks/bias/flats @ ISO 800

 

Seven Sisters

“I have all the all the seven sisters that I need.

I am from Finsbury Park and am having a lark.”

Public Image Ltd (John Lydon et al), This is PiL 2012

220px-PiL_This_Is_PiL

The Seven Sisters chalk cliffs on the Sussex Heritage Coast, one of Britain’s finest unspoilt coastlines.

IMG_2138 (Small)

Seven Sisters London underground station on the Victoria line, in the borough of Haringey

800px-Seven_Sisters_stn_Victoria_line_roundel

Seven sisters – seven major oil companies, which formed the “Consortium for Iran” cartel that dominated the global petroleum industry from the mid-1940s to the 1970s.

fig_002

 

What is it with seven sisters?  Mr Google returns 1,490,000 search results.

444 light years from Earth in the constellation of Taurus, with an apparent magnitude of +1.6, M45 or The Pleiades is one of the most prominent objects in the sky.  To the naked eye, the Pleiades look like a Little Dipper style asterism and with good eyesight it is possible to identify seven particularly bright blue stars.  This ‘young’ open star cluster actually contains over 1,700 stars, dominated by hot, blue stars.  M45 is currently passing through an interstellar dust cloud within the Milk Way, with the blue light from the brighter stars reflected off the dust, thus forming a distinctive blue nebulosity that can be seen surrounding the cluster.

M45 is generally considered to be a winter object in the Northern Hemisphere but, having just passed the Autumn Equinox at the end of September, it can already be seen in the late night / early morning sky.  Furthermore, as we leave the astronomical twilight of summer behind, the darkening skies are a real benefit to astro photographers; pity about the moon at the moment, which lingers until about 2.30am but thereafter leaves a still black sky, perfect for imaging.

Saturday night was the first time I have had to photograph the Pleiades using the new equipment so, given the prospect of a night long clear sky, there was no alternative but to get up early, very early – but it was worth the effort to capture this beautiful star group at its best: M45, the Pleiades AKA the Seven Sisters.

M45, The Pleiades or Seven Sisters star cluster Canon 700D unguided | 26 x 90 secs darks/bias/flats @ ISO 800

M45, Pleiades or Seven Sisters star cluster
Canon 700D unguided | 26 x 90 secs darks/bias/flats @ ISO 800

 

The Witch’s Broom

With polar alignment and tracking now working quite well, I have been hunting around for potential new targets before moving on to the next challenges of computer control and auto-guiding.  Within the constraints of my limited sight lines, light pollution, weather and a rapidly encroaching full moon, I decided to tackle the somewhat elusive Veil Nebula.  Although the apparent magnitude of 7.0 is not unduly challenging, the delicate nature and low surface brightness of this very large ionized gas cloud can make it difficult to image.

Located in the Cygnus constellation, the Veil Nebula is a very large but feint supernova remnant about 1.400 ly from Earth that exploded between 5,000 and 8,000 years ago i.e. quite recently.  The Veil Nebula, Cirrus and Filamentary Nebula usually refer to those parts that can be viewed, the rest of the feature not being in the visible spectrum; the Veil is one of the largest, brightest features in the x-ray sky.  So big is the Veil that various sections are recorded as separate NGC numbers: 6960, 6992, 6995, 6974, 6979 and IC 1340.

Located close to the binary star system 52 Cygni, the classic view is of the Western Veil or NGC 6960, AKA the “Witch’s Broom”, “Finger of God or “Filamentary Nebula”, which spans across 35 light-years and I therefore set out to photograph.  Following the recent success of the North America Nebula I undertook a test shot at the same settings: 90 seconds at ISO 1,600.  However, the resulting picture looked excessively washed out and so changed to 90 seconds at ISO 800, which seemed to work better – though you never really know until the late stages of post-processing.  Despite forecasts to the contrary, the cloud rolled in after just six shots but two hours later and still tracking, the clouds parted leaving a clear sky and just enough time to take another twenty shots.

Initial processing was not encouraging.  Truth be told there’s still a lot to learn with this part of astro-imaging but, with some difficulty and courtesy of Mrs G, a good image of the Witch’s Broom was eventually teased from the data.

NGC 6960 AKA The Witch's Broom Canon 700D | 20x90 sec + darks.bias/ flats @ ISO 800

NGC 6960 AKA The Witch’s Broom
Canon 700D | 20 x 90 sec + darks/bias/ flats @ ISO 800

 

Star wars

A big surprise to me since starting astronomy has been star clusters, which I was strangely unaware of before.  They come in two basic varieties – globular and open – their general nature is, as so many things astronomical, mind blowing.  The Milky Way has about 160 globular clusters, with highly elliptical orbits to the galaxy, whilst more distant galaxies such as M87 have over 13,000.  Each globular cluster typically contains hundreds or even millions of stars held together by gravitational forces in a roughly spherical form, generally packed into regions of ‘just’ 10 ly to 30 ly diameter.

Globular cluster stars are considered to be some of the oldest known objects in the Universe, formed just a few hundred million years after the formation of the Universe itself, and appear to be some of the first produced during galaxy formation.  Most of the stars are red and yellow Population II stars or ‘metal poor’, which have formed after a supernova.  More rare blue stars, known as blue stragglers, may also exist in globular clusters and are thought to be formed in the dense inner regions of stellar mergers.  Notwithstanding, the origin of globular star clusters is still poorly understood but research suggests they may be survivors of galactic mayhem 13 billion years ago.

http://www.mpa-garching.mpg.de/mpa/institute/news_archives/news1202_aaa/news1202_aaa-en-print.html

No known globular clusters display active star formation today, which is consistent with the view that globular clusters are typically among the oldest objects in the Universe and were some the first collection of stars to form.

And so the other evening I turned the camera on a globular cluster, M15 or NGC 7078, located by the constellation of Pegasus.  Estimated at 12 billion years old, it is one of the oldest globular clusters, 33,000 ly from Earth and one of the more densely packed clusters in the Milky Way,  containing some 100,000 stars.  Notably M15 contains a number of variable stars, pulsars, one neutron star and also unusually, a planetary nebula.  All-in-all quite a catch though I am still mystified and intrigued by their occurrence!

M15 Globular Cluster Canon 700D unguided | 20 x 90 secs + darks /   bias / flats @ ISO 800

M15 Globular Cluster
Canon 700D unguided | 20 x 90 secs + darks / bias / flats @ ISO 800

 

Vision Technician

Appearances can be deceiving. WYSIWYG was a term used in 1980’s computing (maybe it still is?) when printing, to indicate that what you saw on the computer screen e.g. formatting and layout, would be the same when printed: What You See Is What You Get.  Being the early days of computing for the ordinary ‘man’, when Microsoft and Apple were just emerging from being start-up companies, the growing choices of hardware and software were not always fully compatible, frequently resulting in a lack of WYSIWYG’ness or put plainly, rubbish printing output.  Even in the 21st century everything is still not WYSIWYG.

I have just completed building and now started to use the new External Astronomy Control Centre (EACC) at Fairvale Observatory.  I am unable to have a full blown, dedicated observatory here at Fairvale, so have to set-up and take down all the astronomy equipment on the patio outside each time I want to carry out viewing or imaging.  It’s a chore, particularly since getting the new and much heavier AZ-EQ6 GT mount and many other pieces of equipment and gizmos; I know this accumulation of equipment and related computing will only continue for the foreseeable future – I am now certain this is an immutable law of astronomy!

Central to controlling all this equipment is the computer.  Currently its main function is for planetarium software and image control and capture: camera settings-up and auto-capture, thus making the large number of images required (subs, darks, bias and flats) less of a chore and, in general, easier to carry out.  I soon hope to extend such computer control to the mount, auto-guiding and tracking correction, plus linking all this to the planetarium for easier navigation.

For the moment this requires that I take my laptop computer outside in order to connect it to the various pieces of equipment, which as the longer, colder nights become more prevalent, exposes it to potentially damaging conditions e.g. dew; I may eventually be able to move the computer inside but for the moment it has to be outside. Furthermore, even using red-screen software to produce a red hue over the computer screen in order to reduce light spilling during image capture (it also helps the eyes to remain adjusted to night vision), the resulting red light is still quite bright and potentially detrimental to imaging.  As a result of these issues I decided to embark on the construction of the aforesaid EACC.

The EACC design needed to be such that it is light, mobile and easy to set-up, whilst primarily achieving two main functions to combat the above problems: (i) protect the computer and leads from the environment – mostly cold and dew, and (ii) as much as possible, contain and thus restrict light spillage from the computer screen.  After detailed consideration of possible designs, the resulting EACC has so far proved to be very successful in meeting these objectives. However, acronyms and fancy names can be deceptive – the EACC is a cardboard box!

EACC in development

EACC in development

EACC completed (there have been a few minor amendments)

EACC completed (there have been a few minor amendments)

Notwithstanding, it is turning out to be a very useful cardboard box.

Other recent cardboard box developments - in this case my daughter Alison's cat Alan looking out of a box, he is particularly keen in attacking and 'catching' feather dusters offered up to the hole.

Other recent cardboard box developments – in this case my daughter Alison’s cat Alan looking out of a box, he is particularly keen on attacking and ‘catching’ feather dusters offered up to the hole.

Of course, it won’t stand up to extreme weather conditions but then I won’t be carrying out astronomical viewing and imaging in such conditions. It has been very successful in restricting light, though it is still important that the AP (AP = access portal = front) is directed away from the telescope in order to direct light spillage away.  Once I had established its usefulness, I sprayed it with a mat black paint to further reduce reflected light and make it a little more damp resistant – it is after all cardboard.  All-in-all a very useful EACC (cardboard box), which however is not what it might at first appear to be – much like the vision technician, or window cleaner!

Last night the EACC in use

Last night the EACC in use

The cunning EACC design usefully deflects computer screen light away from the telescope & camera whilst imaging

The cunning EACC design usefully deflects computer screen light away from the telescope & camera whilst imaging

 

WOW!

Preparation + perseverance = progress, and what progress.

Another clear night last Wednesday, so with my new found success of polar alignment, I started early in the evening in order to try and photograph NGC 7000, or the North America Nebula (it looks like North America).  I had been inspired by images of NGC 7000 on SGL and had already tried a few times to capture it but without success.  With the much improved polar alignment (I went through two star and polar alignment sequences this time) and therefore better tracking, I figured it was also time to increase the stakes overall: a larger set of x20 images (previously 10), speed increased to ISO 1,600 (previously ISO 800), increased exposure time to 90 seconds (previously 30 to 40 seconds) and shooting a full set of additional dark, bias and flat images in order to reduce hot pixels and sensor noise.

And so it was that I managed to successfully photograph the mighty NGC 7000. The very nature of the nebula meant that I did not know if I had the picture until late in the processing phase but it was there.  This emphasises the importance of preparation and the set-up in order to subsequently rely on the scope’s orientation, focus and tracking – you are literally working blind whilst taking a photograph of such an object this way.

NGC 7000 or North America Nebula - after stacking and basic post processing in Photoshop (note aircraft trace).  Canon 700D ( unmodded) | 20x90secs @ ISO1,600 & darks + bias + flat frames, unguided

NGC 7000 or North America Nebula – after stacking and basic post processing in Photoshop (note aircraft trace, subsequently removed).
Canon 700D ( unmodded) | 20 x 90secs @ ISO 1,600 & darks + bias + flat frames, unguided

NGC7000 is located within the constellation of Cygnus, some 1,600 ly from Earth. The North America Nebula is an emission nebula and most of the light emitted is H-alpha (red), most of which is unfortunately filtered out by any normal camera, such as mine the Canon 700D DSLR, by an infra-red filter that is fixed over the sensor.  As a result the basic image captures predominantly OIII (Oxygen Three) light, which is a bluish green colour and is not removed by the camera’s filter.  Many DSO objects have such characteristics and I had been hoping to avoid this problem for a while.  There is a solution, which is to remove the filter, to modify or ”mod” the camera,  the resulting images would then reflect the full light spectrum.  The downside in doing this is twofold, which is why I have not done it to my camera: it’s not cheap to do and it renders the camera useless for normal, earth bound photography! Oh well, something else for the Christmas list.

In the meantime, the red has been put back into the image by using Photoshop. Either way it’s a great image and I am thrilled. Wow indeed!

NGC 7000 North America Nebula, with curves & levels adjustment in Photoshop

NGC 7000 North America Nebula, with curves & levels adjustment in Photoshop

NGC 7000, North America Nembula, with curves, levels and colour balance Photoshop adjustment

NGC 7000, North America Nembula, with curves, levels and colour balance Photoshop adjustment

The devil’s in the detail

The process of DSLR astrophotography can be broadly divided as four main steps:

  1. Preparation – equipment, targets / photographic plan;
  2. Set-up – mount, telescope, camera, control (mount & computer);
  3. Capture – settings (exposure, ISO, f-stop), frames (Subs, darks, bias & flats), tracking;
  4. Processing – stacking & post-processing.

I am only just starting to delve into the final phase, which is another of those black arts and can, which if understood and used well, unlock detail otherwise hidden in each picture.  This is where the difference between film and digital photography becomes most evident.

A digital photo is made up of a series of pixels. Each of the pixels in a digital photo corresponds to a photosite (also called a pixel) on the camera’s sensor.  When hit by light (a photon) the photosite generates a small electric current, which is measured by the camera and recorded in a file – commonly as JPEG or in DSLR astrophotography the RAW format.

JPEG files record the colour and brightness information for each pixel with three eight bit numbers, one for each of the red, green and blue channels.  DSLR cameras (like computers) use the binary system number system (a series of two digits – I or 0); the highest number in 8-bit notation is therefore 11111111.  As a result each eight bit channel records on a colour scale of 1 to 255, or a theoretical maximum of 16,777,216; the human eye can detect between 10 and 12 million colours maximum.

RAW files dedicate more bits to each pixel, which does not equate to more colours but greater tonal graduation – the image is said to have more colour or bit depth.  The theoretical number of tones recorded by my 700D 14bit DIGIC sensor is therefore 4.39 trillion!!!  Post processing such RAW files     therefore has potential access to vast amounts of information, resulting in the possibility of greater detail and subtlety.

At the moment my DSLR processing software is quite basic (relatively, it’s still very sophisticated):

Deep Sky Stacker – used to compile the sequence of original RAW images in order to produce a single, optimized picture containing the ‘best’ data set possible from all the images.  Other correction images may be also combined in this process to reduce such problems as sensor noise but, for the moment, I have limited these to just ‘darks’ (taken with the lens cap on) to help eliminate so-called hot pixels.

GIMP – free online post processing software use to finish the stacked image, by ‘stretching’ the colour ranges levels and adjusting tones and sharpness hitherto unseen detail emerges, often transforming the original photograph; the detail was originally captured by the camera in the RAW file but must be processed in this way to ‘release’ detail that would not otherwise be seen .

Through the application of these techniques modern astrophotography is able to reveal new and transform details of old wonders of the Universe.

Whilst GIMP is very good, a better (more detailed and expensive) post-processing software used in astrophotography and by photographers and graphic designers is Photoshop. Mrs G uses an old version of Photoshop and taking the previous images of M27 and M57 has teased further detail, in particular colour, from these images with great effect. With 4.39 trillion potential colour tones the devil is in the detail and is always worth looking for.

M57 - additional Photoshop post-processing brings out more colour (see previous blog for comparison)

M57 – additional Photoshop post-processing brings out more colour (see previous blog for comparison)

M27 - Photoshop post processing has also 'found' more colour in this image too

M27 – Photoshop post processing has also ‘found’ more colour in this image too

Dialling up the Universe

What a difference a day makes. Following the difficulties of polar alignment the previous day and faced with another great night of clear sky, the only thing to do was to get back on the horse and try again.  I was a little more careful with the basic set-up using two star alignment (Vega & Markab) before attempting the polar alignment again (without the polar scope) using Rasalhague; with the sight-lines at Fairvale Observatory blocked by houses, hedges, trees and the inevitable light pollution, even finding suitable stars is proving difficult and requires some pre-planning.  Following the previous confusion between the Manual and the SynScan handset on this matter, this time I decided to ignore the Manual sections dealing with separate adjustment of latitude and azimuth and, as the SynScan handset instruction prompted, carry out both procedures at the same time.

Having not previously owned the mount’s more basic brother, the EQ6, I am not able to say what all the differences are but, having read reviews of the AZ-EQ6 GT before purchasing, it is my impression that the T-bolt altitude combined with the more traditional azimuth knobs are a new invitation, making simultaneous adjustment of both easier.  For this reason I also suspect that the procedure has been changed in the SynScan firmware (V 3.33), which is not reflected in the Manual; Skywatcher and others please note – these apparently small anomalies can cause great confusion for leaners such as me.  And so it was that this time the polar alignment worked, reducing the error from about +/-3 to less than 10.  Furthermore and notwithstanding my previous point on ignoring the Manual, having re-read the final part of the instructions, it is made clear that on repeating the process the accuracy can be reduced even more.  Therefore after two alignment routines – star and polar alignment – the latitude (MEL) and azimuth (MAZ) polar errors were reduced to a mere few seconds.  This was by far the best I have ever achieved, which was subsequently reflected in the operating accuracy of the mount’s search function (so-called GOTO) and tracking.

I had already experienced the wonder of punching in search objects using the AZ-EQ6 mount – solar, Messier, NGC etc – but with mixed results due to poor alignment.  Now, for the first time with very good alignment, having entered in the desired object the mount slewed gracefully to its location so that on a test camera exposure the object was dead centre in the resulting picture and perfectly focussed.  Another seminal moment in my pursuit of astronomy and imaging the Universe and all its wonders.  I was thrilled, and still am.

Having established this set-up and with a clear sky overhead most of the night, what else was there to do but dial up the Universe using SynScan and start taking pictures, lots of them.  SynScan has an object database of over 40,000, so it might take a while.

M57 Ring Nebula, wide-field view, with polar alignment. Canon 700D | 24x30sec @ ISO1600

M57 Ring Nebula, wide-field view, with polar alignment.
Canon 700D | 24x30sec @ ISO1600

M57 Ring Nebula, close-up with polar alignment. Canon 700D | 24x30sec @ ISO 1,600

M57 Ring Nebula, close-up with polar alignment.
Canon 700D | 24x30sec @ ISO 1,600

M57 The Ring Nebula, cropped from the main image above.

M57 The Ring Nebula, without polar alignment.

M27 Dumbbell or Apple Core Nebula, with polar alignment. Canon 700D | 20x40secs @ ISO800

M27 Dumbbell or Apple Core Nebula, with polar alignment.
Canon 700D | 20x40secs @ ISO800

M27 cropped from previous photograph; it will be interesting to see how much clearer pictures can eventually be obtained with better alingment and longer exposures

M27 without polar alignment

Smoke and mirrors

My brain hurts! The Talking Point section of the recent October edition of the Astronomy Now magazine really poses a serious problem for astronomers, if not the Universe itself; matters don’t get much bigger. The matter being, Is the Universe a Hologram?  It transpires that one of the theoretical consequences of quantum physics and, in particular, very small matter, is that at the smallest scale the Universe may be two dimensional.  The third dimension, emerging in the same sense that an impressionist painting is the macroscopic effect of thousands of spots of coloured paint that, when viewed close up, gives no clue to the overall scene.  I am not making this up.   So serious is this question that Fermi National Laboratory Accelerator Laboratory (Fermilab) in the USA is currently undertaking an experiment to assess the answer; what happens if it is a hologram, do we disappear?  As a result of this devastating possibility, I have read around but frankly am battling to fully understand the concept and its consequences.   http://www.smithsonianmag.com/science/what-universe-real-physics-has-some-mind-bending-answers-180952699/?no-ist

In the event that the answer is in the affirmative, then what have I been photographing out there?

Astrophotography seems to consist of many black arts, not the least of which, in my case, is Polar Alignment. Since getting into this astronomy malarkey I have, wherever possible, taken the easy route – unfortunately this is no longer compatible with my ambitions and I must deal with my astronomy fears: polar alignment, computer control and using a guide scope.  All are essential if I am to improve my pictures and bag some of the more elusive DSOs as well as more mundane objects.  Initial use of the AZ-EQ6 GT mount has already been rewarding through the use of star alignment but without good polar alignment too, a critical piece of information for finding and tracking objects is missing.  In order to track objects across the celestial sphere using an equatorial mount, it is essential to line up the axis of the mount with the Polaris star, which marks the central point around which the celestial sphere effectively rotates.

The AZ-EQ6 GT mount does have a polar scope through which to look directly at the Polaris star and line up the mount.  Alas I cannot use it as my house is directly in the way of Polaris and I don’t really feel like knocking it down, though you never know.  However, there are cunning ways to overcome this problem (i) using another sequence programmed into the mount’s SynScan control handset to achieve polar alignment without a polar scope (see manual #11.3) or (ii) drift alignment, a technique of iterative realignment of the altitude and azimuth by linking the telescope to specific computer software (I believe it can also be undertaken by just using a star trace obtained by a DSLR or CCD camera).

For the moment I am having great difficulty attempting to use the SynScan routine.  Having spent much of Sunday studying the technique, subsequent hours of practice at night brought little success; despite my best attempts, the SynScan handset routine does not seem to be the same as that outlined in the Manual – not a good start.  Sometimes the operation of this complex equipment seems elusively to be driven by smoke and mirrors, let’s hope the Universe fairs better at Fermilab.

M2 Star Cluster; after hours of preparation and attempts to apply the Synscan polar alignment routine, with the P{olar Scope, success proved elusive and tracking poor. Canon 700D | 15x30 sec @ ISO 400

M2 Star Cluster; after hours of preparation and attempts to apply the SynScan polar alignment routine, without the Polar Scope, success proved elusive and tracking was poor.
Canon 700D | 15×30 sec @ ISO 800