Return of the Lion

 

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 2.65o 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 + PHD2 +  Deep Sky Stacker & Photoshop CS3
Image Location              & Orientation Original Subs:  Centre  RA 11h 19’ 44.95”      DEC +13o 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 @ -20oC    
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: 18th + 29th + 31st March + 26th April 2020  @ +21.00h  
Weather Approx. 2 – 8oC   RH 60 -75%              🌙 19 – 43% waxing

Ancient Light

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 2.65o x 2.0o 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 @ -20oC    
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 16th – 27th March 2020  @ +21.00h  
Weather Approx. <=5oC   RH 45-65%                  🌙 <=10% waning

Nice But Dim

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 PNSuch 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?

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 2.65o x 2.0o 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 180o for presentation Top = South     

Exposures 37 x 300 sec  Ha, 25 x 300 sec RGB

Total Time 5hr 10 min   

  @ 139 Gain   21  Offset @ -20oC    
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 11th February 2018  + 2nd &  3rd March 2020  @ +21.00h  
Weather Approx. 5oC   RH <=75%                  🌙 +29% waxing

Jinxed

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 3rd 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 10o  ~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 2.65o 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 + 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 @ -20oC    
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 3rd 2020  @ +21.00h

Panels 5, 6, 7, 8, 9 &14  January 18th 2020  @ +20.0h

Panels 15*,16 & 17* January 19th 2020  @ +19.45h  

*rejected

Weather Approx. 2oC   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 2.65o 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 + 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 @ -20oC    
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 28th 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 1o   ~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 2.65o 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 + PHD2 +  Deep Sky Stacker & Photoshop CS3
Image Location              & Orientation Centre  RA 05:55:38      DEC 01:59:40  @20.49h                     

Image rotated 180o 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 @ -20oC    
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 17th January 2020  @ +20.50h  
Weather Approx. 16oC   RH <=75%                  🌙 29% waning

 

 

Reflections 2019

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 2019 BannerX

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.

RAS logo

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!

wtsm logo

 

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 11th November 2018 coincided with the full lunar eclipse on 21st 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 51o 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 16th 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

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 3o x 1o in 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 3.2o  x 1o  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 2.65o 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 + 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 @ -20oC    
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 22nd & 27th October 2019 @ +/-19.00h  
Weather Approx. 7oC   RH >=75%                  🌙 50% to 5% waning

 

The Sum Of The Parts

Picture saved with settings embedded.

Having established an alternative imaging site at the southern end of my garden in the summer of 2018 AKA The Shed Observatory, I was thrilled to be able to image objects in the north sky for the first time, hitherto obscured by my house from the usual observing location.  Soon thereafter it was with great pleasure I achieved a good narrowband image of IC 1805 the Heart Nebula but was subsequently disappointed to find that part of the neighbouring object, IC 1848 the Soul Nebula, had been missed after encountering a framing problem.

One year on I was back in The Shed with new objectives for these targets: (i) to obtain a complete image of the Soul Nebula, and (ii) given the relative proximity of the Heart & Soul Nebula, to compile a mosaic which included the two objects; surprisingly I’d not attempted a mosaic before and this seemed like a good place to start.  Given the increased imaging time needed to complete even a small mosaic + the lack of darkness at the end of August + British Weather, I chose to restrict imaging to just the Ha-wavelength, which works well with both these targets and could build on the Ha subs already obtained of the Heart Nebula in 2018.

Traditionally mosaic images are based on a grid of say 1+1, 1+1+1, 2 x 2, 3 x 3  etc., which are then combined using the relevant aforesaid sequences, however, in this case starting with the original Heart Ha-subs such a system was not possible.  Since moving to mono imaging with the ZWO ASI1600-Cool camera I’ve used the excellent APT (Astro Photography) image capture software, which hitherto has catered very well with all my needs – including plate solving.  However, at this time APT did not yet have a comprehensive mosaic facility (see footnote) which would allow an imaging grid to be planned and pre-programmed.  Instead it was therefore necessary to first determine suitable image coordinates for each mosaic panel that would cover the Heart & Soul + 25% overlap and then manually establish each position prior to imaging.

Given the proximity of each component I estimated a suitable mosaic could be achieved with three panels, one for each of the main objects and an intermediate panel that would bridge the space between, thus linking the objects to form a continuous mosaic.  Given the spatial relationship, each ofthe three panes needed to be stepped relative to each other and also slightly rotated.  The final data for each nebula consisted of 1h 40m integration time + a further 1h 15m for the link panel, or 4h 35m in total for the complete mosaic.

To my relief the final mosaic was relatively easy to create.  First modestly stretching each panel, paying attention to the background levels and removing any gradients, in order to ensure uniformity between the images before compilation.  I then used Microsoft’s free ICE (Image Composite Editor) software to stich the three panels together into a final mosaic, after which further adjustments were made in Photoshop.

I’m very pleased with the outcome of my first, albeit modest mosaic.  With the ability to return to targets on any occasion using plate solving and, as always weather permitting, multi-image mosaics now open up whole new possibilities which can be captured and compiled over a period of time – even years.  However, until I am able to use a suitable mosaic programme for sequencing, I’m more likely to restrict such projects to small areas that only require limited imaging time, such as the Heart & Soul.

The Greeks and Romans knew a thing or two about mosaics and I’ve long enjoyed Escher’s use of the mosaic form as a basis for his graphic art (see above).  I’m quite sure they would marvel at the astrophotography of Deep Sky Objects and how mosaics can be used in their creation.  The mosaic is all about the sum of the parts, which not only produces a wider, more encompassing view but in doing, so the combined parts add a different quality to the final image.  For now my first mosaic has been quite successful, was good fun and moreover, I can see that the technique ultimately has the potential to open up new and exciting possibilities even with my existing equipment.

Footnote: Since imaging and processing the Heart & Soul mosaic, a recently updated Cartes du Ciel (CdC) verson 4.2 has been released, which incorporates a mosaic planning function.  Moreover, the aforesaid plan can then be imported into the APT software (subject to a minor adjustment being undertaken by APT to fix a panel numbering issue) and thereby provide integrated mosaic planning and programming.   

IMAGING DETAILS – 2018
Object Heart Nebula IC 1805     
Constellation Cassiopeia
Distance 7,500 light-years
Size 150’ x 150’  =  2.5o or 200 light-years
Apparent Magnitude +18.3
 
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 + PS2,  Deep Sky Stacker & Photoshop CS2, HLVG
Image Location              & Orientation Centre  RA 02:33:09    DEC 61:24:23                     

 

Exposures Heart Nebula 20 x 300 sec Ha  =  100 minutes   
  @ 139 Gain   21  Offset @ -20oC    
Calibration 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x Flats Ha  @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 16th & 17th  August 2018 @ +23.30h  
Weather Approx. 12oC   RH <=95%

 

IMAGING DETAILS – 2019
Object Soul Nebula IC 1848   & Link Pane
Constellation Cassiopeia
Distance 6,500 light-years
Size 150’ x 75’  or 100 light-years
Apparent Magnitude +18.3
 
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 + PS2,  Deep Sky Stacker & Photoshop CS2, HLVG
Image Location              & Orientation Centre – Soul Nebula   RA 02:56:16    DEC 60:20:07

Centre – Link Pane         RA 02:43:38    DEC 60:55:59    

Exposures Soul Nebula  20 x 300 sec Ha  = 100 mins   

Link Pane       15 x 300 sec Ha  =  75 mins

  @ 139 Gain   21  Offset @ -20oC    
Calibration 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x Flats HaI  @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 23rd & 25th August 2019 @ +23.30h 
Weather Approx. 18oC   RH <=60%

 

Fireworks

 

HaLRGB final-denoise2-denoise-PS (Large)

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

LRGB.png

M95_96 Anotated

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

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

M101 closeup data crop

M101 widefield data crop

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

M101 HaLRGB crop-denoise-denoisePS

 

IMAGING DETAILS
Object M101  Pinwheel galaxy
Constellation Ursa Major
Distance 20.9 million light-years
Size 28.8’ x  26.9’  or 170,000 light-years  
Apparent Magnitude +7.86
 
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera ZWO1600MM-Cool mono  CMOS sensor
  FOV 2.65o 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 + PHD2 +  Deep Sky Stacker & Photoshop CS3
Image Location              & Orientation Centre  RA 14:03:15      DEC 54:20:46                     

Top = North  

Exposures (A)    L 31 x 180 sec  HaRGB each 16×180 sec                                                                  (Total time:4hr 45 minutes)   
  @ 139 Gain   21  Offset @ -20oC    
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 29th & 31st March 2019  @ +22.00h  
Weather Approx. 8oC   RH <=70%                  🌙  ¼ waning

 

Hunting Orion

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

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

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

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

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

Combined crop 3+5min HaLRGB (Large)

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

IMAGING DETAILS
Object M78 Orion reflection nebula
Constellation Orion
Distance 1,350 light-years
Size 8’ x 6’   
Apparent Magnitude +8.3
 
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera ZWO1600MM-Cool mono  CMOS sensor
  FOV 2.65o 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 + PHD2 +  Deep Sky Stacker & Photoshop CS3
Image Location              & Orientation Centre  RA 05:47:37      DEC 00:20:59                     

Top Left = North  Bottom Left = East 

Exposures (A)    LRGB 8 x 180 sec  Ha 10 x 180sec       (Total time: 1hr 24 min.)

(B)    HaLRG 12 x 300 sec B 17 x300 sec      (Total time: 5hr 25 min.)   

  @ 139 Gain   21  Offset @ -20oC    
Calibration 10 x 180 sec & 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x  HaLRGB Flats               @ ADU 25,000
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5-6
Date & Time 25th  26th 27th February  2019 @ +19.45h  
Weather Approx. 8oC   RH 60 to 80%                  🌙  ½ waning

Eleventh Hour

HaLRGB2FINALcrop (Large)

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

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

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

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

M42 180s Ha StretchNR (Large)

M42 Ha data

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

IMAGING DETAILS
Object M42 Orion Nebula + M43 & Running Man Nebula (SH2-279) etc.
Constellation Orion
Distance 1,500 light-years
Size 65’ x 60’  or 24 light-years (M42 only)
Apparent Magnitude +4.0
 
Scope  William Optics GT81 + 0.80 x Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera ZWO1600MM-Cool mono  CMOS sensor
  FOV 2.65o 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 + PHD2 +  Deep Sky Stacker & Photoshop CS3
Image Location              & Orientation Centre  RA 05:35:09      DEC -05:08:31                     

Top Right = North   Top  = North East   Bottom Left = South   Bottom = South West 

Exposures (A)    L 20 x 180 sec  R 24×180 sec  G 25 x 180  B  24 x 180sec  Ha 17 x 180sec                            (Total time: 5hr 30 minutes)

(B)    12 x 60 sec HaLRGB (Total time: 1hr)   

  @ 139 Gain   21  Offset @ -20oC    
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 23rd 24th 25th February  August 2019 @ +19.40h  
Weather Approx. 7oC   RH <=75%                  🌙 ¾ to ½ waning