Reach For The Sky

October 16, 2020 by grahamrob in AstroBin, Broadband, Deep Sky Objects, Narrowband, Nebula, Processing, Software and tagged Cygnus, LBN325, PixInsight | 3 Comments

In September I returned to the Cygnus constellation, popular for The North America and Veil Nebula at this time of the year but elsewhere often overlooked by astrophotographers. In particular the vast HII-region that is located around the Deneb-Sadr area which contains an abundance of exciting imaging opportunities, this time my target was LBN325 which contains numerous Ha emission nebulae, a dark nebula and a supernova remnant. To capture these features at their best, I chose to shoot, process and then combine separate HaOO narrowband and RGB images for the first time.

Integrating RGB data for better star colours and narrowband data for nebulosity turned out to be tricky but by removing the stars from the narrowband nebulosity and then processing the starless image before combining with RGB image manually eventually worked out well (see top-of-the-page image). However, the narrowband and broadband data had respectively been taken either side of the Meridian without plate solving and unfortunately my manual alignment was on this occasion poor. However, with careful cropping I was eventually able to able to align and combine each of the images, though at the cost of losing 25% of the overall field-of-view which did not overlap; see full size Ha-image below with interesting features along left and right edges which had to be cropped out to align the final narrowband and broadband images.

In addition to LBN325 there are a large number of other notable features (see Image Details table at the end & Nico Carver’s annotated image below – green outline delineates areas of my image). In addition to the many Ha emission nebulae, the most noteworthy are the dark nebula Barnard 345 and a large section of the Supernova Remnant G082.2+53. Some 100 light-years in total diameter, this OIII-rich feature is unfortunately too faint to be picked out in my image, which would require significantly more OIII data to be seen. Looking further afield of the image the continuing richness of the adjoining area cannot be overstated, which is beautifully seen in Nico Carver’s accompanying image (Northwestern Cygnus by Nico Carver is licensed under a CC BY-SA 4.0 License) – an 8-pannel 46-hour mosaic! I can only dream of such work but certainly hope to return to this area again when possible, in order to enjoy more of the exquisite objects that can be found across this truly exciting area of Cygnus. But for now there’s another story about this image.

For some time I’ve known that I had to improve my processing skills and to this end purchased PixInsight software at the beginning of the year. Very few of the best astrophotographers do not use this processing software but PixInsight has a notoriously steep learning curve and no doubt like many others I gave up after a few days! I can unequivocally say that PixInsight is by far the most user unfriendly software I’ve come across in nearly four decades; there’s no denying it’s abilities but the developers clearly gave very little thought to its users. Nonetheless, spurred on by the need to improve my images and the ‘opportunity’ of more time that Covid-19 has provided us all recently, I returned to PixInsight a number of times over the summer and slowly made progress.

Cropped HaLRGB M101 practice image from scratch – using Pixel Math to add Ha has worked within the galaxy but unfortunately seems to have spread into other areas too!

Using my existing data for M101, I first spent many days working through the calibration and integration process, which can only be described as exhausting! Undeterred and in an effort to speed up matters, I moved on to Batch Processing, which though helpful only partially assists the overall task of pre-processing and inevitably put PixInsight aside again in order to find renewed enthusiasm to continue. From this initial experience I had already come to one conclusion – that I would not be using PixInsight for calibration and integration, continuing for now with Deep Sky Stacker and possibly later switching to either Astro Pixel Processor (APP) or Astro Art, both of which get good user reviews.

From the results of others it’s clear that PixInsight is a route to better images and there is no shortage of online tutorials and books but hitherto I’d not found one that worked well for me. Online tutorials by Light Vortex Astronomy are an excellent learning aid but tricky to work with on screen and Harry’s Astro Shed video tutorials were also helpful but I needed a book on the matter to read, thumb through and casually refer to when needed. Then I got lucky!

It was my good fortune that in May a new text by Rogelio Bernal Andreo (AKA ‘RBA’) Mastering PixInsight became first digitally available and then in September was published as a book. The work is divided into two well thought out and presented volumes:

A comprehensive, easy-to-follow and understand description of how to use PixInsight
A reference guide providing more in-depth information on specific PixInsight processes

The two volumes come as a boxed set, are well bound and illustrated and for the first time (from my point-of-view) form an accessible, easy to use and helpful text on PixInsight. RBA deserves every success with this outstanding book(s) which I believe will transform the otherwise torrid experience of learning PixInsight. Armed with RBA’s Mastering PixInsight, Light Vortex Astronomy online tutorials, Harry’s Astro Shed and a other online videos, I’m pleased to say that I am now at last able to use PixInsight for processing and LBN325 is my first image; I should also mention Shawn Nielsen’s excellent Visible Dark YouTube channel, which demonstrates a number of very useful techniques.

As my first attempt to use PixInsight for processing, I’m pleased with the outcome of LBN 325 but realise there’s still much more to learn and, aside from the framing error, it’s clear that even more integration time is needed to get the best of LBN325 and its companions. Going forwards PixInsight and Photoshop both have their respective strengths and weaknesses and judicious use of various techniques from each is probably going to yield the best results. For now, at least, I feel the considerable time put into learning PixInsight is starting to pay off and I’ve finally turned a corner with my processing.

	IMAGING DETAILS
Object	LBN325 & 326 + Barnard 345 & SNR G082.2+5.3 DWB 156, 167, 165, 168, 170, 176,
Constellation	Cygnus
Distance	5,000 light-years?
Size	>2^o
Apparent Magnitude	NA

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWO x8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	APT + PHD2 + DSS + PixInsight + Photoshop CS3 + Topaz Denoise AI
Image Location	Centre RA 20h 18’ 42.55” DEC +46 25’ 03.12”
Exposures	NB 300 sec x 53 Ha & x 38 OIII BB 60 sec x 49 R, x 35 G & x 50 B Time: NB 7hr 58 min BB 2hr 14 min TOTAL 9hr 49 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	Darks 5 x 300 sec & 10 X 60’ 20 x 1/4000 sec Bias 5 x Ha & OIII Flats 10 x LRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	9^th 13^th & 14^th September 2020 @ +21.00h
Weather	Approx. 15-20^oC RH <=60% 🌙 20% waning

The Big Picture

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

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

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

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

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

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

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

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

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

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

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

*Current set-up

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

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

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

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

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

Canine Capers

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

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

CanVen Map

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

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

M51 HaLRGBFinal-denoise-denoise

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

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

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

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

Galactic Bloom

May 15, 2020 by grahamrob in Deep Sky Objects, Galaxy, General Astronomy, Narrowband, Universe and tagged Canes Venatici, M63, Milky Way | 2 Comments

M63 HaLRGB FinalCropRotate3 (Large)-denoise-denoise

You don’t have to be an astronomer to appreciate Van Gogh’s wonderful evocation of the night sky in his 1889 painting Starry Night. He knew a thing or two about sunflowers too and I’ve often stopped by the National Gallery in Trafalgar Square to take a peep at his famous painting of them. However, it was still more than thirty years after completing these paintings that we first learned that such features as galaxies and the rest of the Universe even existed beyond our own Milky Way. Since then our knowledge of the cosmos has expanded considerably and today provides no end of imaging opportunities for the astrophotographer, subject to clear skies!

Having started the galaxy season with M106 and, given the excellent conditions that prevailed throughout much of Spring this year, I chose to return to the same area of the sky again to image M63, AKA the Sunflower Galaxy. M63 has a spiral form but with no apparent central bar and in visible light lacks large scale spiral structure, although two-arm structures are noticeable in near infra-red. Instead the dust lanes are extensively disrupted producing a patchy appearance and is thus classified as a flocculent galaxy – in this case looking something like a sunflower.

As previously discussed, most galaxies are a real challenge for my equipment but an earlier experiment indicated it might just be possible to image M63, the trick would be obtaining sufficient integration time. Fortunately three clear nights approaching a new moon in April provided over 8-hours of good subs, which I’m pleased to say resulted in a decent final image after all. The background sky is less busy than I would wish but there’s nice colour in the stars and also a few very small faint fuzzies on close inspection. Notwithstanding, M63 is clearly the star of the show (no pun intended) with the so-called flocculation clearly evident and numerous random dust lanes criss-crossing the entire galactic disc.

Although in 1924 Edwin Hubble’s recognition that galaxies, such as our own, existed outside the Milky Way, M63 was discovered by Pierre Méchain and catalogued by Charles Messier in 1779, long before Van Gogh’s paintings. He might conceivably have known of its presence therefore but not what it was and would surely be inspired to see and know about the Sunflower Galaxy as we do today.

	IMAGING DETAILS
Object	M63, NGC 5055 AKA Sunflower Galaxy
Constellation	Canes Venatici
Distance	29 million light-years
Size	12.6’ x 7.2’
Apparent Magnitude	+9.3

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 13h 15m 49.47” DEC +42^o 01’ 45.62” Top = North approx..
Exposures	30 x L 17 x R 18 x G 23 x B 12 x Ha x 300 sec Total Time: 8hr 20 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5 x 300 sec Ha + 10 X 300’ RGB Darks, 20 x 1/4000 sec Bias 10 x HaRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	14^th 15^th & 16^th April 2020 @ +22.00h
Weather	Approx. <=8^oC RH 60 – 70% 🌙 40% waning

Return of the Lion

May 2, 2020 by grahamrob in AstroBin, Deep Sky Objects, Galaxy, Narrowband and tagged Leo, M65, M66, NGC 3628 | 2 Comments

Leo LRGB RotateX denoise2 (Medium)

The period between March and May provides an excellent opportunity to see and image objects in and around the constellation of Leo. Located close to the ecliptic, this area of the sky is packed with galaxies and can therefore be seen from most parts of the northern and southern hemispheres. Located to the east of the Leo 1 Group is perhaps the best known of these M65, M66 and NGC 3628, also known as the Leo Triplet.

Leo Constellation

I last imaged this attractive group of galaxies shortly after changing to a CMOS mono camera in March 2017. Unfortunately on that occasion it was only a test with just 45 minutes integration time at 300-gain, so a more serious attempt to image these three beauties was obviously long overdue. On this occasion imaging over three nights during late March and then finally again in April produced well over 7-hours of integration time.

Whilst the earlier test image showed promise, each of these objects is small and certainly push my equipment it to the limit. However, the benefit of much longer time and imaging at unity settings is self-evident. I’m very pleased with the final LRGB image, which shows good detail and colour for all three galaxies. Furthermore, the advantage of a wider view using the William Optics GT81 and ZWO ASI1600MM-Cool camera combination, has also captured numerous other colorful stars and even smaller galaxies, thereby providing a more interesting background for the main show – the Leo Triplet (see below).

Leo LRGB Final (Large)

4184511

Each of the galaxies that make up the Leo Triplet is tilted at different angles relative to the view from Earth, thereby producing a variety of form and perspective in the image (cropped & adjusted to accurate orientation @ top-of-the-page). In addition, various distortions of the galactic discs and other effects demonstrate that the three galaxies in the M66 Group have all been affected by gravitational interactions with each other. Seen edge-on, the unbarred spiral galaxy NGC 3628 clearly shows a broad band of dust stretching along its outer edge, thus obscuring young stars within the galaxy’s spiral arms. NGC 3628 seems to be the most affected by the said intergalactic forces which, moreover, has drawn out a tidal tail from the eastern side of the galaxy spanning some 300,000 light years; unfortunately the aforesaid tail is very faint and does not often appear in images – something for another day and a larger telescope!

	IMAGING DETAILS
Objects	The Leo Triplet or M66 Group: M65, M66, NGC 628 AKA the Hamburger or Sarah’s Galaxy
Constellation	Leo
Distance	35 million light-years
Size	M65 = 8.71’ x 2.45’ M66 = 9.1’ x 4.2’ NGC 3628 = 15.0’ x 3.6’
Apparent Magnitude	M65 +10.3 M66 +9.97 NGC 3628 +9.4

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Original Subs: Centre RA 11h 19’ 44.95” DEC +13^o 19’ 06.48” Main Image Top = East + Cropped Image Top = North
Exposures	180 sec x 42 L Ha, x37 RGB = 153subs Total Integration Time 7hr 39min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec Darks 20 x 1/4000 sec Bias 10 x LRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	x4 nights: 18^th + 29^th + 31^st March + 26^th April 2020 @ +21.00h
Weather	Approx. 2 – 8^oC RH 60 -75% 🌙 19 – 43% waxing

Ancient Light

April 17, 2020 by grahamrob in Deep Sky Objects, Galaxy, Narrowband and tagged Canes Venatici, M106, Ursa Major | 1 Comment

M106 HaLRGB final2 (Large)

Having last year discovered that I could see parts of the zenith region of the sky at Fairvale Observatory (North), in particular Ursa Major and adjacent constellations for short periods during the spring galaxy season, it was an obvious location to return to this year. Furthermore, a protracted period of good weather for most of 12-days coinciding with a New Moon provided an unprecedented opportunity to obtain long integration times on a number of smaller galaxies that abound there.

Following the aforementioned discovery, I was pleased to successfully image M101 AKA the Pinwheel Galaxy in 2019. On this occasion I decided to start with M106 in the adjacent Canes Venatici (“the Hunting Dogs”) constellation, an intermediate galaxy thought to have a supermassive black hole at its centre (see location map and image orientation above). Smaller than M101 with a slightly warped disc and viewed obliquely, it is not an easy target with my equipment but the area also teems with other galaxies and colourful stars that make for an attractive composition; it is intriguing that M106 is of similar size and luminosity to the Andromeda Galaxy M31 but is much further away.

M106 Astromet Names

Taken over five evenings, the final HaLRGB image integration time of nearly 10 hours is the longest I’ve achieved to-date, producing a pleasing image of M106 with good colours and detail throughout the surrounding area (see image at the top-of-the-page). Moreover, across the wider field-of-view a number of other galaxies can be seen clearly, thereby framing the centrally placed M106 and making for a more dramatic image (see annotated kimage above).

Most of the other galaxies vary in age between 20 to 60 million years old, with the edge-on spiral galaxy NGC 4217 thought to possibly be a companion galaxy of M106, however, it is NGC 4226 that I am most excited by. Close to NGC 4217 and resolved only as a small blurred area with my equipment, nonetheless the light from this galaxy has travelled for 334 million years before reaching my camera. The time it left the galaxy we know as the Carboniferous period, when the major coal measures and rocks of the Yorkshire and the Mendip Hills were laid down, a long time before even dinosaurs roamed the Earth – ancient photons from amongst the furthest distance I’ve ever managed to capture on my sensor!

	IMAGING DETAILS
Object	M106 AKA NGC 4258
Constellation	Canes Venatici
Distance	24 million light-years
Size	18.6’ x 7.2’ Diameter 135,000 light-years
Apparent Magnitude	+8.4

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQ-ASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/px Max. image size 4,656 x 3,520 px
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 12:18:58 DEC +47:18:14 North = Left West = Top
Exposures	L x 58 R x 36 G x 36 B x 39 Ha x 20 x 180 secs Total Time: 9hr 27 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec x HaLRGB Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	x5 nights 16^th – 27^th March 2020 @ +21.00h
Weather	Approx. <=5^oC RH 45-65% 🌙 <=10% waning

Nice But Dim

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

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

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

JEL_ITV_ElementFormation_BG-Plate_Updated_23Oct17

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

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

Abell 21 RGB 2018 Final (Large)

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

Ha wavelength

OIII wavelength

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

Abell 21 Combo All 2018 2020 RGB FINAL

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

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

Jinxed

February 24, 2020 by grahamrob in Deep Sky Objects, Mosaic, Narrowband, Nebula, Software and tagged Barnard's Loop, M78, Orion | 1 Comment

Picture saved with settings embedded.

It seems the start of the year has been jinxed, resulting in something of a mixed bag for my astronomy but thankfully not without some positives. A combination of illness, house decoration and some quite awful weather, really curtailed the possibility of any significant astrophotography projects. Despite these difficulties, in the few moments that were available I have managed to carry out some useful experiments which hopefully lay the foundations for greater things the future – clear skies permitting!

Following the success of my first mosaic in 2019, I decided to undertake something more ambitious over the winter, inevitably returning to Orion – specifically Barnards’s Loop. Unseen with the naked eye, the camera discloses the presence of this large arc of ionized gas that is approximately centered on the Orion Nebula, so large that only a conventional wide field camera lens can usually capture the entire Loop. To obtain a higher quality image using a telescope it’s therefore necessary to create a mosaic. With this in mind and keen to expand – physically and metaphorically – my use of the mosaic technique, Barnard’s Loop seemed a worthy object.

BLoop Mosaic PLan

I planned and compiled my previous mosaic of the Heart & Soul Nebula manually but following the recent addition of a mosaic tool to Cartes du Ciel (CdC), which importantly also integrates with my image capture software Astro Photography Tool (APT), this time I was able to plan a 14 (2×7) panel mosaic to image Barnard’s Loop (see accompanying CdC plan above) and the adjacent region. With the ability to vary the overlap and mosaic size up to 10 x 10 panels, once constructed using the CdC mosaic planning the related data is saved to a file, which can then be imported as a series of custom objects into the Point Craft plate solving section of APT; each object is defined by its central RA and DEC co-ordinates. Thereafter, using the plate solving function, the camera and scope are centered one-by-one on each panel for imaging, either manually or by writing a suitable script to automate imaging.

Given the size of the undertaking and difficulties with weather at this time of the year inevitably limiting imaging time, plus the strong Ha-nature of Barnard’s Loop, I chose to confine imaging to only Ha subs, which would pick-out the feature well and thus form a good basis for compiling the final mosaic. The project started well on 3^rd January when I was able to complete imaging the three panels covering the central sections of the large upper arm of the arc, unfortunately thereafter it all went downhill – mostly!

As Orion and therefore the Loop moved inexorably westwards, imaging time became increasingly restricted, further compounded by poor weather and when it was clear, poor seeing conditions. Thus acquisition of the remaining panels became more and more difficult, with many of the resulting panels of only poor quality. All-in all I managed to image twelve of the total 17 panels, adding three to the original plan to incorporate the lower ‘tail’ located between Saiph and Rigel. Whilst the said panels covered the entire feature, such was the poor quality of many they could not be used to achieve the final aim of the project – a Ha-image of the entire Barnard’s Loop.

Using Microsoft’s ICE software, the upper section of the Loop came together well but I’ve not been able to incorporate the middle and lower sections which were of low-quality. I’m quite pleased with the general outcome but consider the project has demonstrated that very large mosaics of this scale are an unlikely proposition at Fairvale Observatory given UK weather conditions and lack of a permanent a setup required to maximize imaging opportunities. Notwithstanding, I believe up to four panel mosaics should be OK – we shall see.

Subsequently the weather was very bad and very, very wet, so unable to image I reprocessed NGC 1333 from last year, which at the time had not come out well. I’d previously noticed that for some reason images had been exhibiting poor quality in the corners, where for no obvious reason stars showed trailing in the processed stacks – though not in the original subs. The solution, thankfully discovered via the Deep Sky Stacking Forum, was to change the Stacking Alignment setting from Automatic to Bilinear and bingo, all was well.

NGC 1333 LRGBx CropF2

NGC 1333 is a colorful reflection nebula located within the dark nebula Rho Ophiuchi, a vast area of gas and dust which is one of the closest star forming regions to the Solar System. In order to evaluate its potential for my equipment I collected just over two hours of LRGB data in January 2019. As previously noted, at the time I was disappointed with the outcome but I now think the revised image processing indicates that with much greater integration time this object could work with more subs – watch this space.

As the bad weather continued throughout most of February there have been very few clear skies but on two such nights I managed brief imaging tests of two other January / February objects which I hope to return to in another year. First of these was another dark nebula Barnard 22, illuminated from behind by the reflection nebula IC 2087. With total LRGB imaging time of just 1hr 24 minutes the processed image was extremely noisy but it was good to see the broad outline of B22 framed well within my FOV and suggests it too could be a viable object for another day.

Finally, with the daffodils already blooming, it was clear that winter was going to be a disappointing time for serious astrophotography, however, I was still able to attempt one final object before the winter night skies receded beyond the western horizon for another year. Surprisingly I had hitherto overlooked this object, visually located just beyond the upper edge of Barnard’s Loop, which though difficult is fortunately also strong in the Ha-wavelength. Lynds’ Dark Nebula (LDN) 1622 AKA the Bogeyman Nebula, describes the somewhat jinxed period I’ve experienced but this time fortuitously brought my earlier work together (x4 panel mosaic below: The Bogeyman – lower left + upper Barbard’s Loop + M78 – top right).

Picture saved with settings embedded.

Despite my best efforts I was unable to see the Bogeyman when framing the image in APT even after stretching but fortunately it still turned out well. I noticed that most other successful images were mainly undertaken in HaRGB, however with limited time before the clouds again inevitably rolled, the few RGB subs obtained failed to add much colour to my image on this occasion. Notwithstanding, with much greater integration time the final Ha-image holds great promise. Furthermore, the said image could be incorporated into the upper main section of the Barnard’s Loop, together with the M78 reflection nebula, to finally make a complete and worthy mosaic image consisting of six panels – see main image at the top of the page and detailed x4 panel mosaic above. Contrary to the name, on this occasion the Bogeyman completed the jigsaw and saved the day!

	IMAGING DETAILS
Object	Barnard’s Loop
Constellation	Orion
Distance	1.434 light-years
Size	10^o ~300 light-years
Apparent Magnitude	5

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Various
Exposures	10 x 5 x 300 sec Ha i.e. 25 minutes / panel or total time: 4hr 10 minutes
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5 x 300 sec Ha, OIII & SII Darks, 20 x 1/4000 sec Bias 10 x Ha, OIII & SII Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	Panels 2, 3 & 4 January 3^rd 2020 @ +21.00h Panels 5, 6, 7, 8, 9 &14 January 18^th 2020 @ +20.0h Panels 15,16 & 17 January 19^th 2020 @ +19.45h *rejected
Weather	Approx. 2^oC RH <=80% 🌙 30% waning

	IMAGING DETAILS
Object	NGC 1333 refection nebula
Constellation	Orion
Distance	1,000 light-years
Size	6’ x 3’
Apparent Magnitude	5.6

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 03:29:07 (23?) DEC 31:28:14 @ +19.16h Top = North
Exposures	6 x 300 sec L&B 7 x 300 sec R&G Total Time: 2hr 10 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5 x 300 sec Ha + 10 X 300’ RGB Darks, 20 x 1/4000 sec Bias 10 x HaRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	28^th January 2020 @ +19.15h
Weather	Approx.? RH <=? 🌙 9% waxing

	IMAGING DETAILS
Object	Lynds’ Dark Nebula (LDN) 1622 AKA Bogeyman Nebula
Constellation	Orion
Distance	500 light-years
Size	1^o~10 light-years?
Apparent Magnitude	?

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 05:55:38 DEC 01:59:40 @20.49h Image rotated 180^o for presentation Top = South
Exposures	19 x 300 sec Ha, 4 x 300 sec RGB Time: Ha only 1hr 35 min Total 2hr 35 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5 x 300 sec Ha + 10 X 300’ RGB Darks, 20 x 1/4000 sec Bias 10 x HaRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	17^th January 2020 @ +20.50h
Weather	Approx. 16^oC RH <=75% 🌙 29% waning

Reflections 2019

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

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

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

Heat Map 2019

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

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

Overview, Images & Goals for 2020

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

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

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

Favourite Images

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

SHO2 CompF (Large)

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

M101 HaLRGB final Closeup

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

Picture saved with settings embedded.

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

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

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

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

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

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

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

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

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

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

Watch this space!

2019 CHRONICLE

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

JANUARY TO MARCH

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

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

HaLRGB2FINALcrop (Large)

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

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

NGC 2024 Ha Starless2

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

APRIL TO JUNE

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

LRGB Image FINALX2 (Large)

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

LRGBFinal (Large)

JULY TO SEPTEMBER

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

SHO2SCcrop (Large)

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

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

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

SHO F HLVG (Large)

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

IMG_2345 ComboX

OCTOBER TO DECEMBER

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

HaLRGBx5b (Large)

ASTROMINAGING RECORD 2019

No	Date	Type	Object	Name

1	21/01/19	DSLR	Full Lunar Eclipse

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

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

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

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

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

7	29/03/19*	Combo	M101	Pinwheel Galaxy

8	10/04/19	Combo	M51	Whirlpool Galaxy

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

10	16/07/19	DSLR	Partial Lunar Eclipse

11	02/08/19	NB	NGC 7380	Wizzard Nebula

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

13	26/08/19	NB	NGC 281	PacMan Nebula

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

15	Sept	DSLR	Milky Way	Split Mountain Utah

16	22/10/19*	Combo	M31	Andromeda Galaxy

17	18/11/19	BB	M74	Galaxy

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

*multiple evenings Combo = HaLRGB Underlined = BAA published

POSTSCRIPT

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

RHB_2ajelly (Medium)

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

M95_96_105 (Medium)

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

IMG_2336 (Large)

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

M74 LRGBx (Medium)

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

SH2-240 AB combined Ha Stretch (Large)

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

One In A Trillion

December 7, 2019 by grahamrob in Broadband, Deep Sky Objects, Galaxy, Narrowband and tagged Andromeda, Milky Way | 1 Comment

HaLRGBx5b (Large)

Since the early twentieth century when Edwin Hubble recognized that the Milky Way was not the only galaxy, it has been estimated that there are some two hundred billion galaxies in the observable Universe; the Milky Way is thought to contain about 250 billion stars +/- 150 billion. Research in 2016 now suggests this might significantly underestimate the number of galaxies, which could exceed more than two trillion!

Perhaps the ultimate astrophotograph is the Hubble Ultra Deep field image. At just one seventeenth a degree of the sky in size it shows objects up to some 13 billion light-years away, which is the furthest visible light image ever taken and contains some 10,000 galaxies.

Somewhat closer to home at a mere 2.5 million light-years, is our nearest neighbour M31, AKA the Andromeda galaxy. Like the Milky Way, Andromeda is a spiral galaxy with a concentrated bulge of matter at the centre, surrounded by a disk of gas, dust and stars and an immense halo. Andromeda and the Milky Way are moving inexorably together on a collision course at the rate of about 70 miles per second and are expeted to meet in about 4.5-billion years. However, such is the space between the matter in each galaxy, the most likely outcome will not be a collision but the interaction of gravity between the opposing masses, leading to their eventual coalescence into a new giant galaxy.

Since starting astroimaging I’ve often returned to Andromeda at this time of the year ( 21/08/14 Meet the Neighbours, 09/10/15 Space Oddysey, 27/10/15 Overspill, 03/11/17 Galactic Neighbours), it is after all one of the magnificent features of the night sky. At some 3^o x 1^oin size, with an apparent magnitude of +3.44 the galaxy completely fills the field-of-view of my equipment but I’ve always found imaging and particularly processing to be somewhat challenging. As ever integration time is a major determinant of final image quality and this time I was able to obtain 7.5 hours over two nights, far greater than on previous occasions. However, the overwhelming brightness of the galaxy’s core is always difficult to control during capture and processing and this was again to be the case.

Notwithstanding, I’m pleased to say that after four previous occasions imaging Andromeda, the combination of much greater integration time and better processing is this time evident in an improved image, which is overall more powerful. Moreover, the galaxy’s internal structure has been enhanced with the addition of Ha-subs, which highlight large HII-areas of star formation that broadly follow the dust lanes. However, you can never have too many subs and I’ll inevitably return again to this object in order to add to this year’s data and hopefully further improve processing so as to tame the subtleties that make Andromeda such a wonderful feature for astrophptography.

	IMAGING DETAILS
Object	M31 the Andromeda galaxy.
Constellation	Andromeda
Distance	2.5 million light-years
Size	3.2^o x 1^o or 220,000 light-years
Apparent Magnitude	+3.44

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600M M-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker & Photoshop CS3
Image Location & Orientation	Centre RA 00:42:44 DEC 41:16:04 Top = North
Exposures	L 44 x 180 sec R 26 x 180 sec G 26 x 180 B 27 x 180sec Ha 27 x 180sec (Total time: 7hr 30 minutes)
	@ 139 Gain 21 Offset @ -20^oC
Calibration	10 x 180 sec & 15 x 60 sec Darks 20 x 1/4000 sec Bias 10 x HaLRGB Flats @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	22^nd & 27^th October 2019 @ +/-19.00h
Weather	Approx. 7^oC RH >=75% 🌙 50% to 5% waning