Eastern Promise

SHO Final

Eastern Veil Nebula NGC 6992 & NGC 6995 in SHO narrowband*

The East traditionally evokes connotations of the exotic and a promise of excitement.  This year the late Summer delivered plenty such opportunity for astrophotography combined with long, warm and clear nights, making for a productive and very enjoyable time.  Furthermore, this being the first year I’ve owned the mono ZWO1600MM-Cool camera, I’m mostly revisiting objects previously imaged with a modded DSLR and as a result am discovering details of hidden interest and beauty within the new images; on this occasion the object of my desire was the Eastern Veil Nebula in the Cygnus constellation.

Desperate to start re-imaging suitable targets with the ZWO camera, I briefly flirted with the Eastern Veil on the morning of the summer solstice this year.  But with limited darkness of any sort and coming just before dawn, imaging time was very limited.  I was still pleased with the result which bode well for longer, darker night conditions with the potential for extended imaging time.  In June I was only able to capture 18 minutes of Ha and 9 minutes each of OII and SII wavelengths, compared this time with a whopping 30 minutes for each!  OK it’s still quite short and for a standard CCD camera might only amount to one or two subs but given the unique sensitivity of the ZWO1600 operating at -20oC – itself a game changer in so many ways – the additional integration time achieved resulted in much more detailed and dramatic images than before.

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Eastern Veil Nebula in Ha-OIII BiColour*

For the moment I’m very pleased with the outcome but it’s obvious that greater imaging time holds the prospect of even better images – although such improvements are likely to be less dramatic and more incremental in nature.  Due to practical limitations at this site I’m limited to about 2-hours dedicated imaging time each side of the Meridian and will only be able to increase the integration time beyond this barrier by using plate solving, thus enabling meridian flips during a session or cumulative imaging of the same object over different nights.  With plenty to learn and enjoy with the ZWO1600 camera, plus Orion already reappearing over the eastern horizon – my personal favourite, this is unlikely to occur before next year.  In the meantime, the Eastern Veil points towards a very promising future – Watch This Space!

NGC 6992 Bicolour The Eastern Veil Nebula detail in Ha-OIII BiColour*

Bicolour FINAL BAT

The Bat Nebula IC 1340 detail in Ha-OIII Bicolour*

IMAGING DETAILS*
Object Eastern Veil Nebula   AKA Caldwell 33      NGC 6995, NGC 6992 & IC1340   
Constellation Cygnus
Distance 1,470 light-years
Size Approx. 80’  vs Total Veil Nebula 3o
Apparent Magnitude +7.0
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control
Guiding William Optics 50mm guide scope
+ Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera ZWO1600MM-Cool (mono)   CMOS sensor 
FOV 2.65o x 2.0o   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,  Deep Sky Stacker & Photoshop CS2
Exposures 10 x 180 sec Ha, OIII & SII  (Total time: 90 minutes)
@ 300 Gain 10 Offset @ -20oC  
Calibration 5 x 180 sec Darks 10 x 1/4000 sec Bias 10 x Flats Ha, OIII & SII  
Location Fairvale Observatory – Redhill – Surrey – UK
Date & Time 19th August 2017 @ 22.38h

 

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Pelican Brief

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Located 3o west of the star Deneb in the Cygnus constellation, the North America Nebula is an emission nebula spanning some 50 light-years across, which contains numerous areas of astronomical interest that form some excellent imaging targets.  In the past I’ve usually concentrated on the ‘continent’ of North America itself but on this occasion moved my attention off the ‘east coast’ in search of the distinctive Pelican Nebula – it really does look like a pelican!

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North American Nebula (left) & Pelican Nebula | WO GT 81 & modded-Canon 550D | 2015

Separated from its neighbour by a molecular cloud of dark dust, the dominant HII region of the Pelican Nebula responds well to Ha imaging and I therefore sought to capture the ‘bird’ in this and other narrowband wavelengths.  Detail within the main cloud is further highlighted as a result of ionization from within created by young star formation, making for some pleasing and often spectacular effects.

Whilst image capture went well I was concerned by the outcome of stretching the Ha-image after stacking; the stacked image in DSS looked bright and detailed but after using Levels in Photoshop to establish the dark and light points the resulting image was somewhat dull in appearance and without the finer detail I had previously seen in DSS.  Responses to a question on the SGL Forum post made it clear that I needed to be bolder when stretching in order to achieve the desired result; I am further persuaded that I’ve been too timid with such processing techniques in the past and may need to revisit and reprocess some older data when time permits.

Pelican Images 10th August 2017 in order below:  

Ha – Bicolour – SHO narrowband

WO GT81 & ZWO1600MM-Cool + x0.80 focal reducer | 180 sec Gain 300 Offset 10 @ -20C 

10xHa + 10xOIII + 5x SII + full calibration    

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I went on to process the full narrowband data in both SHO and Bicolour, with interesting results.  The aforementioned assessment of linear stretching resulted in a much improved Ha-image, which subsequently impacted positively on the final compiled image.  However, there’s still much to consider when processing the combined channels, in particular in narrowband.

Some aspects of manipulation used during processing can have a material impact on the final image and I’ve long been concerned whether the resulting astrophotography presents a factual representation – in the case of narrowband the answer must surely be no.  Depending on the quality of data capture, detail and structure will usually be accurately recorded but subsequent ‘playing’ with the colour channels is most likely to produce a final image that is pleasing aesthetically to the photographer rather than factual; in the case of narrowband the colours available will be correctly determined by the respective filter wavelengths but there is no definitive measure of what actual colour should be in the final image.

RGB2crop (Large)In this case the Ha-image of The Pelican that was obtained demonstrated the significant improvements that can be achieved with the CMOS based ZWO1600MM-Cool camera compared to a DSLR.  I’m still learning about processing and in particular, with the plethora of options available when using LRGB and narrowband subs the issues have now escalated exponentially.  Notwithstanding the aforementioned issues I’m very pleased with my ‘new’ bird The Pelican Nebula.

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New Broom

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Converting from a DSLR to the ZWO1600MM-Cool camera feels in part like I’m starting out all over again and is exciting.  I’m getting used to the new field-of-view and its implications for framing, which is complicated further by using separate mono filters that can often make it difficult to identify on screen the chosen imaging target.  I’m also learning to use Astro Photography Tool (APT) for image capture, which is turning out to be an excellent programme, though at times somewhat idiosyncratic in nature.  APT contains useful Histogram and associated Stretch tools, which when applied to test shots prior to data capture can reveal underlying target detail which is otherwise unseen and thus enables suitable framing to be chosen.

With a set mount location, better polar alignment, calibrated PHD2 and a basic star alignment model established in EQ-ASCOM early in the summer, the process of imaging has now become much more efficient. After adding a few supplementary alignment points local to the target and some other minor adjustments, I have recently been able to set-up and start imaging in much less than one hour; excluding the physical set-up, imaging is possible within 30-minutes.  Contrast this with one or two hours when previously using various Synscan handset procedures and setting up the DSLR camera, I think it’s fair to say I have at last crossed the proverbial Rubicon!  Using a cooled sensor and compiling a calibration library has also been very helpful in streamlining imaging sessions, which all-in-all has made my astrophotography much more productive – qualitatively and surprisingly quantitatively too, despite all the extra subs and calibration required.

I’m currently working through familiar targets with Ha-OIII-SII subs to produce Hubble Palette based images.  It’s true to say that the use of narrowband filters has also been nothing less than a revolution for my imaging, in terms of process and results.  I’m particularly pleased that I purchased the ZWO x8 EFW and matching LRGB + narrowband filters with the new camera – 31mm parfocal filters also help minimize the need to re-focus for different wavelengths.

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The Witch’s Broom (NGC 6960): WO GT81 & Canon 700D camera + 0.80x Focal Reducer | 20 x 90 sec + calibration @ ISO 800 | October 2014

It’s about 4-years since I embarked on my nascent astrophotography journey and soon thereafter I first attempted to image the notoriously difficult Veil Nebula – which of course is why I had to try.  At the time I did not know one end of the Veil from the other of this very large but faint and widely dispersed supernova and was pleased to achieve a recognizable image of the Western Veil or Witch’s Broom (NGC 6960).  This July I set out to re-image the same feature for the first time using the ZWO1600MM-Cool camera in narrowband.

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The Veil Nebula AKA Cygnus Loop: Ultraviolet view ref. NASA

The full extent of the Veil is broadly demarcated by the Western and Eastern Veil Nebulae, with other generally more diffuse but related areas in between.  All-in-all the entire feature is some 3o or 110 light-years across.  The ZWO1600MM-Cool has two notable features that differentiate it from conventional CCD mono cameras, those being larger sensor size and high sensitivity when using only short exposures.  Unity of the sensor is 139 but like many other new users I’ve successfully been using a much higher Gain, in my case 300 with an Offset of 10; others have reported very good results as high as 600 Gain at just 30 second exposure, which though data heavy is very useful in helping to circumvent the UK’s fickle weather conditions and the need for perfect polar alignment, which was a major factor in deciding to purchase this type of mono camera.

Being still unfamiliar with the camera’s field-of-view using the William OpticsGT81 refractor and x0.80 focal reducer combination, on this occasion I centred the Broom just above the centre of the frame, thus adding the possibility of capturing other parts of the nebula located to the east and just below the Broom in this case.  As I’ve yet to master or even attempt mosaics or a Meridian flip with plate solving, for the moment my imaging is limited by the transit period defined from about 110o east to the Meridian or similarly to the west and between a 30o to 80o azimuth, which equates to just over 2 hours per target each side of the Meridian.  The nature of the object and lack of darkness at this time of the year can often restrict this available time even further.  Notwithstanding, on this occasion I was able to obtain 20 x Ha and 18 x OII 180 sec subs in order to produce a final bicolour image.

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The Witch’s Broom NGC 6960 & Pickering’s Triangle NGC 6979 Ha-OIII-OIII Bicolour: WO GT81 & ZWO1600 + 0.80x Focal Reducer | 180 sec x 20 Ha & 18 OIII Subs + calibration @ Gain 300 , 10 Offset & -20C | 31st July 2017

With a good set of subs the stacked and collated Ha-OIII image has turned out well, with nebulous filament details typical of the Veil that had not previously been clear when using a modded-DSLR camera now clearly visible.  Furthermore, on this occasion the aforesaid framing included detail of both the Broom and as something of a bonus Pickering’s Triangle, altogether forming a very pleasing image.

At this stage I would usually crop the Witch’s Broom and finesse the resulting image in Photoshop.  However, following a prior line of thought and questioning on the SGL Forum, this time I tried to use the Drizzle_technique during stacking to enhance the quality of The Broom itself.  Unfortunately it didn’t take long to discover that, as so often is the case with astrophotography, drizzling is a good deal more complicated than just placing a check in the Drizzle box.

Originally developed for use with the Hubble Space Telescope, drizzle is a digital processing method for the linear reconstruction of under-sampled images, thus improving the apparent resolution of the image.  Deep Sky Stacker is an excellent piece of software and provides the facility of x2 and x3 Drizzle but unlike some commercial packages has limited memory that is used for this task.  As a result after attempting to use Drizzle whilst stacking a number of times in DSS, the process crashed at the end of each sequence.  Finally another SGL Forum query provided the answers: (i) DSS lacks memory required to stack and process the original sub using Drizzle, but (ii) Drizzle will work by applying the Custom Rectangle Mode in DSS to a select a specific, smaller area of the sub.  It took me a while to figure this out but eventually I manged to process the Witch’s Broom area of the image successfully.  I’ve concluded that Drizzle is certainly a feature worth deploying during stacking from time to time but only where the main target is poorly sampled and where the specific object will fit within the Custom Rectangle Mode defined by DSS – it should also be noted that the resulting data size also increases very substantially when using Drizzle.

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Witch’s Broom (as above) + 2x Drizzle

All-in-all it continues to be a great surprise just how different and often complex the techniques are with a mono camera and filters compared to a one-shot DSLR camera, both during capturing and processing.  I was previously aware of these issues and some related shortcomings but so far the results have justified the additional effort; I’m not sure I would say the same about a conventional mono CCD camera, that requires much longer imaging times which in my opinion are not suitable for the average user and weather conditions in the UK.  I know there’s still much to master – Plate Solving + Mosaics + Meridian Flips + Sequence Generator Pro etc. – and I’ll soon need to start a completely new alignment star model for winter and recalibrate PHD2 guiding but the past few months have really been good fun and very productive.

Cosmic Nursery

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With the summer arm of the Milky Way now starting to dominate the late evening sky I’m slowly returning to imaging DSO objects, this time literally in a new light using the ZWO1600MM-Cool camera.  Because of the inclined orientation of the Milky Way it is the lower altitude objects that first become accessible, which is unfortunate as seeing conditions will generally always be poor at these levels.

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However, the problem is compounded here at Fairvale Observatory by high hedges and numerous large trees that obscure much of the southern horizon below about 28and in this case also severely restricting imaging time.  It’s a real pity as the constellation Sagittarius that is located in this region of the sky abounds with some wonderful objects.

M20 Location

On this occasion my primary target was M20, the Trifid Nebula (NGC 6514). At some 28” size and an apparent magnitude of +6.3 it is just feasible with my equipment, so long as I could overcome the obstructions along the southern horizon!  Located 5,000 light-years from Earth in the Scutum spiral arm of the Milky Way, at about 300,000 years old M20 is one of the youngest star forming regions in the sky.  The feature is a combination of open star clusters, emission nebula and reflection nebula separated by dark dust lanes, that together form three lobes i.e. Trifid.  As a stellar nursery, close to the centre the most massive star is twenty times the size of the Sun surrounded by a cluster of 3,100 young stars.

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M20 Trifid Nebula & western edge of M8 Lagoon Nebula in Ha-OIII bicolour | WO GT81 & ZWO1600MM-Cool camera + 0.80 focal reducer | 180 sec x10 Ha x5 OIII x3 SII + full calibration Gain 300 Offset 10 @ -20C | 27th July 2017

 

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M20 Trifid Nebula in Ha-OIII Bicolour (cropped)

Despite the limited imaging time available and other difficulties, I’m pleased with the resulting images, which have been processed in SHO and Ha-OIII bicolour.  Furthermore, just evident along the left side of the main image is the western edge of the much larger Lagoon Nebula or M8; unfortunately being even lower in the sky I don’t think I’ll ever be able to image M8 from this location.

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M20 Trifid Nebula in SHO narrowband (cropped)

Together with the recent success of the Eagle Nebula and Eastern Veil, things are shaping up well for astrophotography once again as the Milky Way and other features pass across the night sky over the coming increasingly dark weeks.  I’m certain to return to M20 again as it’s a wonderful object, hopefully from a better vantage point next time that will allow imaging of some of its neighbours.  I have long been aware of M20 and in my ignorance was going to call this blog Gardener’s World but now realise that it is the Trifid not Triffid nebula!

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That’s Trifid not Triffid!

 

The Dutch Gadget

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I have just finished reading J.L. Heilbron’s biographical tome on Galileo, which though very interesting I found a difficult book and somewhat academic in style.  In 1609 Galileo became aware of a Dutch spectacle maker’s device that made distant objects appear closer.  He subsequently became known for developing the so-called ‘Dutch Gadget’ into what we now know as the refracting telescope and moreover, applying its use to understanding the Solar System with the discovery of Jupiter’s four largest moons, confirmation of the phases of Venus and the observation and analysis of sunspots; the word telescope was subsequently coined in 1611 from the Greek tele “far” and skopein “to look or see” i.e. far-seeing.  In so doing he also helped to confirm the then controversial truth of the heliocentric astronomical model, whereby the Earth and planets orbit the Sun.  Against this background it is no surprise that Galileo is today much revered by mankind and has become known as the father of observational astronomy.

GalBook

Drawn into the complexity of obtaining images of the Solar System and beyond, it is the curse of astrophotography that we inevitably neglect observing the spectacle itself.  Notwithstanding, I am sure that Galileo would understand the power and beauty of today’s astrophotography, which in its own way is producing a quantum leap in our understanding of the Universe comparable to the impact of the original application of the telescope.

This summer the Solar System will hopefully provide both good observational and astrophotography opportunities here at Fairvale Observatory: Jupiter, Saturn, Comet C/2015 V2 (Johnson), the Perseids meteor shower and the Sun – sadly though I will not witness next month’s solar eclipse which takes place mainly over North America.  During recent summer months the lack of astronomical darkness, short nights and absence of DSOs has frustratingly continued to limit potential imaging targets for my new ZWO 1600MM-Cool camera but utilising a period of good weather there have recently been a few fleeting opportunities just before dawn related to the appearance of the summer arm of the Milky Way on the eastern horizon.

solstice sky

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NGC 7000 The North America & Pelican Nebulae WO GT81 + modded Canon EOS 550D + FF | 30 x 120 secs @ ISO 1,600 + calibration | 19th September 2015

I first imaged the North America Nebula (NGC 7000) in 2014 and have since returned each year to image the nebula or its various parts using a DSLR camera.  Being a very large Ha-object the nebula is an ideal target for the ZWO1600MM-cool camera and I have been anxiously waiting its arrival again this year.  On this occasion, early on the morning of the summer solstice, high in the sky and 90o east the nebula was only just visible from my location, being very close to the roof-edge of my house!  Consisting of just six Ha-frames plus three OIII and SII taken just before dawn broke, the resulting image was never going to be my best but is nonetheless interesting in SHO format and quite different to previous DSLR images.

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North America Nebula in Ha-OIII Bicolour

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North America Nebula in SHO

At the other extreme, located low on the southern horizon and only briefly visible as it passed between the trees at the end of my garden is the Eagle Nebula AKA M16, home of the Pillars of Creation.  At 7-arcminutes in size and an apparent magnitude of +6.0, the nebula is at the lower end of possible for my set-up and at some 27o altitude with just 40-minutes imaging time between the trees it was a challenging target.  Notwithstanding, I’m pleased with the Ha and SHO narrowband images obtained, which quite clearly show the Pillars too.

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M16 Eagel Nebula in SHO: William Optics GT81 & ZWO1600MM- Cool & Field Flattener | 6 x 180sec Ha, x3 OIII, x3 SII Gain 300 Offset 10 + full calibration | 21st June 2017

As astronomical darkness is now slowly returning and with clear skies and weather permitting, I hope to attempt longer imaging sessions of both these and other targets during the rest if the summer and into autumn – I might even get to see M16 again as it eventually emerges from the other side of the trees!  Thanks to the development of the Dutch Gadget and modern cameras it is now possible for amateur astronomers to image such spectacular objects – I’m sure Galileo would be impressed and highly approve.

Another Side Of the Veil

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Veil Nebula / Cygnus Loop WO GT81 & modded Canon 550D + FF | 30 x 180 sec exposures @ ISO 1,600 | 19th September 2015

I first imaged the Western Veil in October 2014 and return each year to the so called Witch’s Broom and other parts of this faint supernova remnant that stretches over 3-degrees of the night sky for the next four months.  Located in the Cygnus constellation, the Veil Nebula is high in the sky and at this time-of-the-year is only just visible late in the night being some 80o east of The Meridian; short nights and lack of darkness further complicates imaging at the moment.  However, with the weather set fair and having just completed some other good targets, I couldn’t resist a few frames of the Eastern Veil using the new ZWO1600m-Cool camera and narrowband filters before going to bed.

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

With Nautical Darkness due to end at 2.40 a.m. imaging time was at a premium. In the event I managed just 40 minutes, towards the end of which the sky perceptibly lightened – it was after all mid-summer day and the Summer Solstice beckoned!  The limited imaging time inevitably impacted on the quality of the final image but I am nevertheless pleased to have seen and imaged another side of the Veil nebula so soon in the year on 21st June – certainly the sensitivity of the camera helped a lot in achieving this.

Veil HSO Hub

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Veil Bi Col Hub

Bi-colour Ha+OIII+OIII

Eastern Veil Nebula – narownband images: All images taken using WO GT81 + Field Flattener & ZWO 1600MM-Cool camera + either Ha (6 x 180 sec), OIII 3 x 180 sec or SII 3 x 180 sec at -20C set at Gain 300, Offset 10 & full calibration | 21st June 2017 

I am still experimenting with narrowband imaging and therefore using colour mapping processed the three wavelengths into three different final image formats.  The HSO and Ha-OIII Bi-colour are interesting but my favourite is the SHO version shown below, which shows interesting and attractive details of the Veil’s nebulosity in ways that were previously not possible with a DSLR camera.  Though short, it was a very productive evening for imaging and for a variety of reasons will be a night to remember for a long while.

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Eastern Veil Nebula in SHO – For Will

 

A New Palette

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It still remains early days with the new ZWO 1600MM-Cool camera but the initial signs using the narrowband filters have been very promising and frankly good fun.  I’ve been surprised at the benefits gained using these filters and especially the new and exciting possibilities it introduces to imaging. But there’s more.

When first using a digital camera for astrophotography it came as a surprise to discover that the colours come from an RGB Bayer Matrix placed in front of the sensor.  The so-called One Shot Colour camera or OSC, provided me with many decent images and when I recently started to think about getting a better camera another OSC seemed the way to go.  Their major benefit is that you are able to just take, as it says, one shot – or multiple colour shots for stacking.  Of course there’s still much to learn when starting out but the process is relatively simple and a decent set of subs and calibration frames can be obtained in a few hours or less; subsequent processing is also straightforward with one set of subs and no more than three sets of calibration frames.

Notwithstanding, when looking at more specialized OSC cameras, it soon became clear that the benefits of moving from DSLR were limited.  Another surprise with astrophotography is that the best images are obtained using a mono camera, in combination with colour and if required narrowband filters.  Hitherto, this has meant precise guiding in order to obtain long exposures using a very expensive CCD camera.  However, last year everything changed with the introduction of completely new technology in the form of a cooled CMOS camera, which I and the astrophotography community are currently getting to grips with – the aforementioned ZWO ASI1600MM-Cool.

Whilst more complex to use than a DSLR, this camera seems to be something of a game changer for astrophotographers in that: (a) it has a larger more sensitive sensor than a CCD camera, (b) it’s cheaper (though not cheap), (c) because of its sensitivity imaging requires only relatively short exposures, thus reducing the need for ultra-precise guiding as it gathers light more quickly than a conventional camera.  It was the latter feature that convinced me to go ahead with the camera and it is already clear this was not a mistake.

I often complain about the excessive cloud cover we suffer here at Fairvale Observatory, which can often prohibit imaging for weeks or even months on-end.  The advantage of imaging quickly when the clouds do eventually part is therefore a major factor for me.  If the camera has one problem it’s probably the vast quantity of data generated, putting huge demand on computer memory and processing power – but it’s worth it.

LRGB

LRGB imaging is the main format used by most advanced astrophtographers, after all the resulting colours and detail achieved can be spectacular and it was now time for me to give it a try.  I was astonished to learn that some 80% of the detail in an image is in the luminance and only 20% colour, so the advantage of LRGB imaging becomes immediately apparent.  I also purchased the ZWO x8 EFW and matching 31mm filters with the camera and initially had some problems getting it to work.  However, once sorted it has been a pleasure to use and makes image sequencing with different filters a piece of cake.

At the moment I’m using Astro Photography Tool (APT) for capture and apart from my own lack of LRGB imaging experience and some misunderstandings of the software, it works very well.  A full LRGB sequence is easy to set-up beforehand and after that the imaging automatically looks after itself!  I carry out most of the calibration frames manually but this too is generally quite easy; I did struggle at first with the flats, which is a quite different method compared to a DSLR but once I got the hang of the APT Flats Aid – courtesy of the APT Forum members – all was OK.

Notwithstanding, at first I was concerned by large concentric light and dark halos in the flats.  I have long used the combination of a flowerpot, LED and T-shirt for taking flats, which has always worked well.  I therefore expected the flats from the new camera using APT would not be a problem.  However, as mentioned taking flats with this camera is a whole new ball game which has taken some time to master, or at least learn.

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The flower pot flats set-up has always worked well before.

Unlike the DSLR, which just requires changing to the AV mode, it is necessary to calculate an exact exposure – to five decimal places – using a mid-range ADU setting of between 20,000 and 25,000 for each different LRGB filter.  Sounds awful and it does generate a lot of frames but now I’ve got the hang of the Flats Aid it is much easier and very effective; on average I have so far found the required exposures vary from 0.00145 sec to 0.00792 sec.  I did discover some minor light leakage in the optical train when testing the flats taken in daylight but by doubling up the T-shirt material and adopting a more careful set-up of the flower pot directly in front of the telescope object lens, the halos now seem to have disappeared.

The other new ‘toy’ with this camera is cooling.  Despite the camera’s low noise and high sensitivity, like all digital cameras there is an inevitable amount of unwanted signal and currents created by the sensor.  Apart from applying calibration frames, this problem can be significantly reduced by cooling the sensor when imaging.   APT also has cooling and warming aid controls to avoid thermal shock but at first I struggled to get these working – turns out I forgot to plug the power lead in!  After that it has worked like a dream and I am now routinely imaging at -30oC.  The one drawback is that cooling down and warming up adds another 10 or 15 minutes to the set-up and take-down times, which can be annoying at 2.00 a.m. when you want to get to bed!

Unfortunately, now I have this camera working suitable imaging targets are in short supply for the moment.  At first I was able to carry out some narrowband imaging of the remaining late winter nebulae just before they disappeared for the season but I must now wait for a few months until later in the year for similar objects to appear again. Meanwhile, whilst the night sky in spring abounds with some wonderful galaxies, most of these are really too small for my set-up to resolve properly.  However, in the absence of larger DSO objects I have had to make do with these and have been pleasantly surprised by some of the results obtained.

The outcome of Leo Triplet and Markarian’s Chain were particularly good and demonstrate the superior abilities and power of the camera.  Compared to the Canon 550D, when used with the William Optics GT81 refractor and a x0.80 field flattener, the ZWO 1600MM-Cool’s sensor produces a notably larger image with much greater sensitivity.  As a result detail of all three galaxies that form the Leo Triplet M65, M66 and the end-on view of NGC 3628 is quite apparent and in another image, the spirals of the very small M61 galaxy can be clearly seen, though the quality is poor.

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Leo Triplet – M65 (top right) M66 (centre right) NGC 3628 (lower left) Leo Constellation: William Optics GT81 & ZWO 1600MM-Cool + x0.80 field flattener | 60 sec 20 x L, 5 x RGB + full calibration, Gain 300 Offset 10 @ -20C | 21st March 2017

As expected the size of the data set from LRGB imaging with the camera is prodigious and furthermore, requires great care to organise before processing if mistakes are to be avoided.  In the case of Markarian’s Chain I experimented with binning – only to learn later that it has no effect with CMOS sensors – which reduced the file size of the RGB and calibration images.  Nonetheless, in all there were still 140 images with a combined file size of 1.6 Gigabytes!  Notwithstanding, the benefits of LRGB imaging with this camera and EFW outweigh such problems and nowadays an extra storage disk is relatively inexpensive.  Only processing power could perhaps be a problem if using an older PC but my 64-bit + i7 chip +16 GB RAM laptop computer has so far dealt easily with data processing very well.

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The difference between imaging and processing with a DSLR and the ZWO CMOS mono camera has been much greater than I anticipated and required more adjustment which I am still dealing with – the learning curve is steep!  Notwithstanding, the experience previously gained using a DSLR has proved invaluable and I would not like to take-on LRGB imaging from scratch; I’d like to think that my adage of walk before you run once again has paid off.  This camera is very exciting and I am confident that when the autumn and winter skies eventually return the new palette now in my hands will reap great rewards – can’t wait.

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Markarian’s Chain | Subs 60 sec – see table for details Gain 300 Offset -30C | 18th April 2017

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M61 piral Galaxy in Virgo Cluster | William Optics GT81 & ZWO 1600MM-Cool + x0.80 field flattener | L 30 x 40 sec RGB 3×20 sec + full calibration Gain 75 Offset 15 -30C | 2nd April 2017

Brave New World

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In my quest to understand astronomy and in particular the big picture, I have just successfully completed another MOOC course at the University of Edinburgh on the Higgs Boson and particle physics.  From earlier studies which included the Special Theory of Relativity and the Universe, the next step was obvious: moving from the very big to the very small in order to better grasp where we might be with the elusive unified theory and I was not disappointed. An added bonus to the course was the participation of Professor Peter Higgs himself, in which he discussed how he had arrived at his conclusions and the development of subsequent matters that led to the actual discovery of the Higgs Boson at the Large Hadron Collider in Cern, Switzerland in 2012; watching and listening to him speak felt like having a personal chat with Einstein and was quite a privilege!

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A chat with Professor Peter Higgs!

Frankly I found the nature of the subject very difficult and at times bewildering but its potential impact on astronomy was finally something of an epiphany for me.  The Higgs and related items results in two profound results:

  • There was no Big Bang.
  • The existence of a multiverse, of which our Universe is but a part.

I am not sufficiently able to articulate how these conclusions are arrived at nor is this the place, but when the full content of particle theory, the Higgs, General Relativity are applied to cosmology, the aforementioned outcome is, like all good science, simple and beautiful – click here for lecture notes Higgsmooc part1  + Higgsmooc part2  and accompanying presentations 7.11_Quantum Vacuum_& Cosmology + 7.12_The HB_scalarfieldsand inflation.

I’m pleased to say there have also been other breakthroughs for me since achieving first light with the ZWO 1600MM-Cool CMOS camera.  I am still at the experimental stage and with the spectacle of the winter sky rapidly departing, suitable objects are much more limited, with the few remaining HII objects low and very far to the west of the early evening sky.  However, before the Milky Way disappeared completely I managed to obtain some useful imaging experience by targeting some old favourites.

M42

Passing Shots: Orion & Rosette Nebulae

Having already battled a number of issues with the new camera – basic LRGB image capture, using Astro Astronomy Tools, achieving focus, guiding, alignment, processing and post-processing – for the moment everything has come together, including some warmer nights and clear skies.  Over a few evenings I therefore undertook imaging in LRGB as well as Ha, OIII and SII, with some excellent results that augur well for the future.

The camera’s sensitivity and ability to image at short exposures enables much less imaging time than conventionally used with CCD cameras – one of the reasons I decided to purchase this camera.  In addition, shorter exposures make perfect alignment and tracking less important, though still a desirable set-up.  The downside is it produces a prodigious number of images, which leads to a somewhat challenging processing burden – but it’s worth it.

Despite my DSLR experience, CCD processing and especially post-processing, is significantly more complex.  I was surprised to find only one decent online video on LRGB processing by Rankin Studio, without which the task would have been even more difficult and taken much longer to learn – thanks David.  Ironically I have found narrowband processing easier, probably because there are just less filters and resulting image sets required, however, the restricted wavelength also provides whole new opportunities that I’ve already started to exploit.

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Orion Nebula + M43 & Running Man Nebulae in Ha: William Optics GT 81 & ZWO 1600MM-Cool + x0.80 field flattener | 15 x 180sec Gain 139 Offset 21 @ -18C & full calibration | 25th March 2017

Just before they disappear from our night sky until next winter I was fortunate to be able to image both the Horsehead and Orion nebulae, everyone’s favourites and I’m no exception.  With limited time available in the early evening sky it was only possible to capture a limited number of images before it moved outside my view in the west but even with these few images the power of the camera has already become self-evident.

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Horsehead Nebula in Ha: William Optics GT81 & ZWO 1600MM-Cool + x0.80 field flattener | 19 x 180 secs Gain 139 Offset 21 @ -18C & full calibration | 27th March 2017

Given the need to use less filters and thus less time I have started out with narrowband imaging – as a completely new medium for me that holds great promise aesthetically and scientifically, I was also keen to give it a try and on this occasion used Ha and OIII.  Having sorted an earlier problem with the EFW managing the filters is a breeze and can easily be automatically sequenced in the APT capture software.  Notwithstanding, as previously indicated image capture is really only just the start – though good data is always the key to the final image – and processing and post-processing is both complex and takes considerable time.

M42 Bicolour & balance

Orion Nebula in bi-colour: Ha red channel + OIII green and blue channels

On this occasion the individual Ha subs are themselves very revealing, showing new details when compared with previous DSLR images.  But it is with the bi-colour image that the exciting opportunities provided by using narrowband imaging become apparent – I can see I’m going to enjoy this!  I’ve also taken the opportunity to further explore and understand the nature of these types of images and their constituent parts by manipulating the colour channels, with some startling results.

NGC 2244 HOS-1LCLCrop (Large)

Rosette Nebula in HOS: William Optics GT 81 & ZWO 1600MM-Cool + x0.80 Field Flattener | 15 x 180 sec Gain 300 Offset 10 Ha, OIII & SII @ -20C + calibration | 24th March 2017

Not far from M42 is another of my favourites which I’d already used to achieve First Light with this camera using Ha – the Rosette Nebula (NGC 2237, 2238, 2239, 2244 & 2246).  This time I decided to use all the narrowband filters – Ha 656nm, OIII 672nm, SII 500nm all 7nm bandpass – and subsequently experimented with processing using the Hubble Palette with stunning results.  As the name indicates, this technique was originally developed for processing images taken with the Hubble Space Telescope which put simply, uses different mixes of each narrowband filter in different processing channels e.g. Ha in the red channel, OII in green and SII in blue, for short known as HSO.

NGC 2244 SHO Final1

Rosette Nebula in  SHO

The outcome of my new adventure into narrowband imaging has been nothing less than a revelation.  Like so much of my preceding astroimaging, I knew about much of it before but doing it yourself and seeing the results is both exciting and very satisfying; like Peter Higgs I feel I have entered a new world!

Headhunter

 

The latter part of 2016 was very productive, especially around the end of November and early December.  Remarkably the clouds were completely absent for over a week, it was cold but the air was unusually dry and furthermore it was only just past the New Moon, all-in-all excellent conditions for astrophotography.  With Orion starting its Christmas-New Year parade across the night sky it was also a good time to investigate other parts of this fascinating constellation which I had not previously imaged.

Depicted in Greek mythology as Orion the Hunter, attention is most often given to the ‘sword’ that hangs from his belt – formed by three open star clusters which notably includes M42 the Orion Nebula.  Located just above, in the eastern region of the Hunter’s so-called belt and is NGC 2014 the Flame Nebula and the nearby Barnard 33, or as it is more famously known – the Horsehead Nebula.  I have imaged these and other targets such as the reflection nebulae M78 just above the aforementioned Flame Nebula and the difficult to image IC 2118, better known Witch’s Head nebula, situated just beyond the bright star Rigel which forms the Hunter’s left foot.

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

However, a much wider view of Orion shows the presence of very large regions of HII nebulosity enveloping the main constellation, which altogether form the Orion Molecular Cloud Complex.  Most notable of these areas is Barnard’s Loop, a large HII cloud that arcs across some 10o of the sky encircling the lower, eastern section of the Orion star asterism.  I have had some limited success imaging the Loop before but on this occasion I tried some of the other areas of HII nebulosity which are located within the higher parts of Orion the Hunter.

The combination of the William Optics GT81 and their x0.80 field flattener reduces the focal length from 478mm to 387mm and increases the speed from f5.9 to a fast f4.72.  Apart from removing distortion at the periphery of the image, when used with the Canon 550D DSLR the field flattener increases the field-of-view by a staggering 64% or from 2.67o x 1.70o to 3.34o x 2.23o.  This has its shortcomings when imaging galaxies which generally have a small FOV but is perfect for large DSOs such as my first target.

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The basic ‘anatomy’ of the Hunter is outlined by a number of stars that form his legs, waist and arms, with a club held above in his right hand and either a shield, lion’s pelt or bow held outstretched in his left hand.  On this occasion I first attempted to image his head; catalogued as SH2-264 it is otherwise known as the Lamda Orionis Nebula or sometimes the Angelfish Nebula. This very large HII cloud is located, as would be expected, at the top of the Hunter’s body and should be a good target for the aforementioned equipment with a modded camera, now aided by the longer exposures from my newly found PHD2 guiding expertise.

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Upper Orion constellation & Lamda Orionis setting

This HII-feature is broadly centred on the giant double star Meissa or Lamda Orionis, which is itself at the apex of a triangle with the red giant superstar Betelgeuse to the east and blue giant star Bellatrix to the west and thus forms the outline of the Hunter’s shoulders. Some 8o in its entirety, the Lamda Orionis Nebula is enormous but consists mainly of very faint Ha-light, so that despite good imaging conditions, long exposures and good framing I was unable to obtain any sign of its presence on this occasion.

Frankly I was surprised there wasn’t at least a vestige of red Ha-light somewhere in the image but for now I will have to admit defeat.  However, looking back I can see the Hunter’s head in previous wide-field nightscapes of Orion taken in January 2015 and 2016.  Notwithstanding, together with other nearby stars Meissa forms the open star cluster Collinder 69, which on this occasion fortunately produced something of a pleasant alternative image.

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Meissa double star & Collinder 60 open star cluster | William Optics GT81 + modded Canon 550D & 0.80 FF + Guiding | 14 x 300 secs @ ISO 800 & full calibration | 4th December 2016

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Subsequently I slewed the telescope and camera to another, nearby HII-cloud, this time situated along the Hunter’s right arm, just above his elbow.  Discovered by amateur Californian astronomers Harold and Charles Lower in 1939, at about 45’ x 45’ size H2-261 or Lower’s Nebula is much smaller than the Lamda Orionis Nebula but also faint and difficult to image.  However, here I did manage to capture something of the Ha-feature, albeit that the image was rather noisy when processed and yes I did apply Gradient Exterminator, though it doesn’t look like I did.

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Lower’s Nebula SH2-261 | William Optics GT81 & modded Canon 550D + FF + guiding | 12 x 30 sec @ ISO 800 | 4th December 2016

The Orion Molecular Cloud Complex is one of the best known areas for star formation that is closest to Earth and provides an abundance of wonderful imaging targets at this time of the year.  However, as previously experienced with Barnard’s Loop, the large areas of HII cloud that encircle much of Orion’s constellation can be elusive and difficult to image, which will probably require a camera of greater sensitivity and many more exposures to achieve success.  However, on this occasion the image of Lower’s Nebula was some consolation as I continue my quest for Orion’s scalp.

Reflections – 2016

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

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

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JANUARY TO MARCH

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

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

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Monkey Head Nebula

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

  • When working in the dark and worse still in the cold, the ergonomics and general convenience of operating the equipment becomes paramount.  Since starting to use EQMOD-ASCOM and Cartes du Ciel for mount control and tracking, I encountered the problem of having to be in two places at the same time; in this case co-ordinating adjustments at the mount and the computer, in particular when making and syncing star alignments.  The answer to this conundrum was a gamepad, which I purchased for a nominal sum on eBay and after watching the inimitable Chris Shillito’s video on setting up and using a gamepad with EQMOD-ASCOM, have never looked back.  By using the gamepad the telescope can now be manually slewed, centred and synced on any object whilst remaining at the scope, thereby making the process of alignment much quicker and convenient.
  • At the end of 2015 it was my intention to start guiding in the coming year, a prerequisite for the long exposures necessary to increase data capture and thus hopefully improve image quality.  I had originally intended to use my ZWO ASI120 MC camera together with a William Optics 50mm guidescope for this purpose but there always seemed to be other problems to overcome first and to be honest, I was somewhat intimidated about tackling the black art of guiding.  I was finally prompted to do something about this when in March a second-hand Starlight Express Lodestar X2 autoguide camera came up on the UK Astronomy Buy & Sell.  From previous research I knew this was considered to be a very good and popular guiding camera, so as it had only just been posted on the website, I immediately went for it and was successful – timing is everything.  Inevitably I had problems setting-up and in particular getting the camera to focus – which was my own fault – but by the end of March I was guiding!  Truth is my guiding at this stage was not very good and I needed to look further into using the PHD2 guiding software but nonetheless, the equipment was at least now working together!

No

Date Object*

Name

1 07/01/16 Orion Barnard’s Loop
2 14/01/16 Orion Barnard’s Loop
3 02/02/16 Catalina Comet
4 02/02/16 Milky Way  
5 10/02/16 IC 2087 Dark nebula
6 NGC 2174 Monkey Head Nebula
7 IC 2177 Seagull Nebula

*Record of quarterly photographic images taken in 2016

APRIL TO JUNE

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

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

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

IMG_6235 (Large)

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

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

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

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

No

Date Object

Name

8 April USA Monument Valley etc
9 06/06/16 M5 Globular cluster
10 M13 Globular cluster
11 M57 Ring Nebula

JULY TO SEPTEMBER

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

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

No

Date Object

Name

12 07/08/16 M16 Eagle Nebula
13   M11 Globular
14   B142-3 Dark E-Nebula
15 11/08/16 Perseids  
16 23/08/16 LDN 673 Dark Nebula
17   NGC 6781 Planetary Nebula
18   M27 Dumbbell Nebula
19   Albireo Double star
20   Moon  
21 28/08/16 M11 Globular cluster
22   NGC 6905 Blue Flash Neb
23   Albireo Double star
24   15 Aquilea Double star
25   NGC 6960 W Veil / Witch’s Broom
26   M32 Andromeda Galaxy
27 29/08/16 M27 Dumbbell Neb
28   NGC 6960 W Veil / Witch’s Broom
29   NGC 7814 Pegasus galaxy
30   M15 Globular
31   M27 Dumbbell Nebula
32   M27 Dumbbell Nebula
33 08/0916 M27 Dumbbell Nebula
34   M27 Dumbbell Nebula
35   NGC 6960 W Veil / Witch’s Broom
36   NGC 6960 W Veil / Witch’s Broom
37   M31 Andromeda Galaxy
38 11/09/16 NGC 6888 Crescent Nebula
39   NGC 6992 Eastern Veil  (NGC 6995)
40 13/09/16 M57 Ring Nebula

OCTOBER TO DECEMBER

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

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

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

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

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

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

No

Date Object

Name

41 22/10/16 M15 Globula cluster
42   M33 Triangulum Spiral Galaxy
43 28/11/16 M45 Pleiades
44   NGC 2024 Horsehead Nebula
45   M42 Orion Nebula
46 29/11/16 Hyades Open star cluster
47   NGC 2244 Rosette Nebula
48 30/11/16 NGC 1499 California Nebula
49   IC 405 Flaming Star Nebula
50 03/12/16 M74 Spiral Galaxy
51   M77 Spiral Galaxy
52   M1 Crab Nebula
53   IC 2118 Witch’s Head
54   M78 Reflection Nebula
55 04/12/16 SH2-264 Lamda Orionis
56   SH2-261 Lower’s Nebula

ETCETERA

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

TTT Cover

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

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

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

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

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

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WTSM: The Book!

Favourite Images

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

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

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

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B142/3 Barnard Dark E-Nebula

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

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

 

Round-up & goals for 2017

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

RECORD CARD – 2016
Goal Specifics / Results Outcome
Increase imaging exposure times Improved equipment set-up and alignment and successfully started autoguiding with exposure times of up to 8-minutes. DONE

 

Improve processing Started using newer version of Photoshop CS2 + other related software. Improvement with post-processing using online tutorials and Nik Syzmanek’s booklet Shooting Stars. GETTING THERE

 

Start widefield imaging Purchased Vixen Polarie, with portability put to use in the USA but did not make UK dark sky sites as planned. GETTING THERE

 

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

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

  • Improve processing: As the headmaster’s report would say “room for improvement” and I will try.  I have purchased Warren Keller’s book Inside PixInsight, considered by many to be the gold standard of post-processing software but is a nightmare to learn – this may be a step too far for now, we’ll have to see – maybe 2018?
  • Expand and improve widefield imaging: First – use the Vixen Polarie as had been intended last year to obtain nightscape images at UK dark-site locations.  Second – look at ways of using a widefield set-up with the mount more successfully.
  • Start LRGB imaging: I spent a lot of time in 2016 considering the question – what next? I am keen to image smaller DSO objects, in particular galaxies and was on the verge of purchasing a larger telescope – probably another refractor.  However, after attending a talk by Nik Syzmanek, one of Britain’s foremost astrophotographers, I have come to the conclusion that the next step should probably be a move to LRGB imaging, which if successful probably has the greatest potential to improve my pictures – let’s hope so.

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

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

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

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

Watch this space!