Jumbo Joy

Picture saved with settings embedded.

After recently establishing Fairvale Observatory South AKA “The Shed” and dealt with some expected and unexpected problems, I was able to turn my attention to the object of my desire in this hitherto inaccessible part of the northern night sky.  With the summer solstice approaching I had originally planned on imaging this astrophotographers’ favourite later in the year but I couldn’t resist an early look.  A few nights after finishing Bodes galaxy from my new, northward looking location, I therefore swung the scope across the Meridian to the north east in order to obtain a few subs of this object just to see: (a) what it might look like with my equipment (b) bearing in mind the previous objective, to assess the best framing and (c) just for the fun of it, and was not disappointed!

RGB XXX Final (Large)The aforesaid object of interest was the Elephant’s Trunk Nebula or IC 1396, a very large emission nebula, which in narrowband shows wonderful colour and detail (HaSHO above).  IC 1396 consists of glowing gas illuminated by an open star cluster, broken up by intervening lanes of dark interstellar dust clouds.  The ‘trunk’ itself, designated IC 1396A, is the long dark area protruding from the lower edge of the image, spectacularly illuminated from behind by a bright star forming region; the image has been rotated 180o from its natural position.  Top right on the edge is the red supergiant Mu Cephei or Herschel’s Garnet Star, one of the largest and brightest known stars in the Milky Way, which in the position of the Sun would extend out to Saturn’s orbit!

HHOO (Large)

The large IC 1396 nebula will not fit my field-of-view but with some judicious framing, using the Garnet Star as a marker and helped by a few previously taken test subs, I achieved a pleasing composition with the aforesaid trunk and nearby billowing dark clouds well placed (HaOIIIOIII bicolour image above).  Whilst I am pleased with my first attempt at the Elephant’s Trunk, the colour could be better and is too noisy – a consequence of too little integration time and high gain setting.  Having had success before using similar settings for Ha-type features like the Rosette Nebula, I was a little surprised by this outcome but it just goes to show that each object is different.  Notwithstanding, the Ha version is – I think – very promising (top of the page) but obviously there is too little OIII and SII in the composite wavelength images.

RGB XXX Final Crop (Medium)

I used to live and have worked all over Africa but this is a very different type of elephant to what I have met before (the “trunk” HaSHO above).  It forms an exciting imaging subject at this time of the year, made all the more rewarding being one of my first serious attempts to image the north sky.  I hope to return to this object in a couple of months when astronomical darkness has resumed but in the meantime the Jumbo of the night sky has been a real joy on my first encounter.

Elephant Location Crop

IMAGING DETAILS
Object Elephant’s Trunk Nebula   IC 1396   
Constellation Cepheus
Distance 2,400 light-years
Size 5o or “Trunk” only approx.. 45’   
Apparent Magnitude +3.5 to +5.7
 
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
Image Location Centre  RA 21:38:37    DEC 57:30:16  
Exposures 12 x 300 sec Ha + 6 x300 sec OIII & SII  (Total time: 120 minutes)   
  @ 300 Gain   50 Offset @ -20oC    
Calibration 5 x 300sec 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
Date & Time 22nd May 2018  @ midnight
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Boreal Breakthrough

M81 A (Large)

I have often written about imaging difficulties here at Fairvale Observatory, which apart from overflying aircraft from Gatwick and Heathrow airports, 24/7 helicopters from Redhill aerodrome and general light pollution, also consists of numerous sightline obstructions in the form of large trees to the east and south, high garden hedges and the complete obstruction of the north sky by my house!  I have toyed with the idea of moving onto the lawn so as to look back northwards over the house but was concerned by all the faffing about to get the equipment down and back up a flight of steps, as well as added complications with equipment control and dew problems; I concede that many do operate successfully in this way but with plenty of other problems to cope with, I like my hobby to be as easy and convenient as possible.

Last year I enjoyed working outside during the summer months – notwithstanding the lack of darkness during much of this period – and therefore over the past winter finally considered how such a garden-based set-up could be achieved, primarily for use between May and September.  The resulting Plan-A was to place three paving stones within the lawn to support the tripod and run a USB-cable back to the house for control.  However, after recently expanding a small paved area outside the shed at the end of the garden and looking at the potential sightlines from this location, it was obvious that a Plan-B set-up here could also work.  Whilst not quite as good viewing angles as the original location, there are a number of other worthwhile benefits:

  • Being off the lawn on paving it seemed likely that dew could be less of a problem;
  • Working on the paving around the mount would be more convenient and dry;
  • By clearing out the adjacent shed it could be used as a dry location from which to control the equipment.

And so early in May I set about establishing Plan-B and soon afterwards putting it to work.

Pan1 Comp (Medium)

The view from the shed looking northwards is surprisingly quite good (see above) and I don’t know why I hadn’t considered this before. There are a few large trees to the north east, a high hedge along the western boundary and of course my house is still somewhat in the way but altogether it’s not too bad and for the first time I have a clear view of Polaris, as well as a whole new plethora of imaging targets!  Whilst this direction looks directly towards south London, being on the southern slope of the Greensand Ridge the worst of the city’s glow is fortunately obscured by the hill.  Furthermore, it is ironic that my house and the hedges also provide considerable protection from the local street lights, which I’m pleased to say are now turned off after midnight anyway.

Set-up

Local equipment layout the same as previously

I cut-back some of the adjacent vegetation to improve sightlines and ran a power cable from the house to the shed otherwise it’s exactly the same set-up which was being used at the main, south looking location on the patio by the house.  I looked into WiFi-control of the equipment but from the experience of others concluded it could be unreliable and instead considered using Teamviewer software via a USB Cat-5 repeater cable from the mount / shed computer to a second computer in the house.  However, given the distance of some 30 metres I finally decided to adopt a more robust LAN Cat-6 ethernet cable for this purpose. Unfortunately whilst this had worked successfully during testing in the house, I have so far been unable to get it to work outside and for now have had to operate the equipment from inside the shed, which has nonetheless proved to be a comfortable and effective alternative.

Being lazy and cautious about changing too much about the set-up, I levelled, aligned and reset the new location data of the tripod but kept all other settings the same for now.  I realise this is not ideal but initially just wanted to experience the new location and north sky to understand what was possible within the given field-of-view and identify any obvious problems.  Fortunately a settled period of good weather allowed me to try out the new location soon thereafter.

North Sky ViewX

White area shows optimum imaging area from Fairvale Observatory South – AKA ‘The Shed’

What I hadn’t expected on first use was that slewing and tracking would become more difficult and takes noticeably longer at higher latitudes, especially approaching Polaris.  Following subsequent enquiries and with some further thought it now makes sense.  At higher latitudes near and above about 70 degrees as the lines of Longitude are closer together, it makes the RA slew rate bigger and bigger the closer you get to the North Celestial Pole.  Of course the celestial pole is not coincident with the terrestrial pole, which means that those objects within the latitude of 90o minus the observer’s latitude – in my case this equals 39o – means that all those objects above 39o will be circumpolar from my point-of-view i.e. will rotate over the year around North Celestial Pole.  This is basic astronomy but hitherto I had not considered the implications for tracking and guiding before and will need to bear it in mind when selecting targets in the future.

M81 B (Large)

I had one particular target in mind but as it was only viable much later in the night, on this occasion I chose to start imaging the north sky for the first time with Bode’s Galaxy AKA M81 and the nearby Cigar Galaxy AKA M82; for comparison using low gain, long exposure on the first night (top of the page) and high gain, short exposure (below) on the following night.  Given the target’s DEC position of 70o I soon discovered the aforesaid tracking difficulties, which resulted in the RMS guiding error varying from 3’ to 20’ and deleterious consequences for the images!

 

Whilst I’m pleased with my very first north sky images, it is obvious I’ll need to return again with better guiding and much longer integration time.  On a positive note the general set-up worked very well and the shed provided an excellent place from which to operate the control and image capture equipment.  Furthermore, despite a few restrictions the overall view of the northern night sky is good and holds much promise for future, hitherto inaccessible imaging objects.  As a result of establishing this new site I intend to name the new north looking location Fairvale Observatory South or ‘The Shed Observatory’ (see mosaic above) and the principal, south looking location by the house Fairvale Observatory North or ‘The Patio Observatory’.  Altogether this marks a major breakthrough for my astronomy and I eagerly await the return of astronomical darkness on 20th July onward.

AstroNet ResultX

IMAGING DETAILS
Objects Bode’s Galaxy M81  &  Cigar Galaxy M82     
Constellation Ursa Major
Distance M81  11.8  &  M82  11.4 -12.4 million light-years
Size M81 26.9’ x 14.1’   &    M82 11.2’ x  4.3’
Apparent Magnitude M81 +8.0  &  M82 +8.4
 
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
Image Location Centre Image-B    RA 09:55:13.46    DEC 69:21:08.36  (19/0518) 
Exposures                       

                                       

                                         

A 18/05/18   10 x 180 sec L  + 5×180 sec RGB  (Total time: 75 minutes)    @ 139 Gain   21  Offset @ -20oC

B 19/05/18   45 x 60 sec L    + 15 x 60 sec RGB  (Total time: 90 minutes)    @ 300 Gain   50  Ofsett @ -20oC    

Calibration                    

                                        

A 15 x 180sec Darks  20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU 25,000  

B 15 x 60sec Darks     20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU 25,000  

Location & Darkness Fairvale Observatory South – Redhill – Surrey – UK       Typically Bortle 5
Date & Time (A)    18th  &   (B) 19th May 2018 @ +23.45h approx.

 

 

Star Struck

 

M13 LRGB F2 CROP (Large)

Of all the things I’ve discovered since taking up astronomy, perhaps it is the presence and nature of globular clusters that has most surprised me. Bound closely together by gravity, these massive spherical collections of stars orbit the galactic core perpendicular to its plane.  In the case of the Milky Way there are 150 globular clusters but they can be much larger in other galaxies, such as M87 which has some 13,000; clusters of clusters have also now been discovered in the Universe!  Typically each cluster might contain a few thousand or tens of thousands of stars, although in some cases they can be much larger.  Omega Centauri is the largest globular cluster in the Milky Way, being 150 light-years in diameter it contains 10 million stars; though clearly visible from Earth it can only be viewed from the Southern Hemisphere, which we unfortunately did not see when in New Zealand earlier this year.

MW & globs

Despite all the advances being made in cosmology, the origin of globular clusters still seems to remain quite uncertain.  Characteristically the stars are all very old, typically in the region of 8 to 12-billion years and are of low metallicity i.e. they contain a low proportion of elements other than hydrogen and helium.  At least some, such as Alpha Centauri, are thought to have condensed from dwarf galaxies and such a process may currently be taking place within the large Magellanic Cloud – which we did see in New Zealand!  In other cases it is thought that the clusters have probably originated independently and were subsequently captured by the relevant galaxies.  However, their very old age – sometimes nearly as old as the universe itself – origin and relationship to galaxies remains intriguing.  For these and many other reasons I personally find globular clusters fascinating, probably more than any other astronomical feature, amazing as they too may be.

GlobsX

Globular Clusters May 2018: M3, M13 & M92 (red circles) + Others (yellow circles)

From time-to-time I’ve tried imaging various globular clusters but have not been satisfied with the outcome.  Now using guiding, plate solving and the high-resolution ZWO1600MM-Cool camera, it was time to give it another try this spring, when some of the best clusters are present in the northern night sky.

M3 LRGB Final (Large)

First up was M3 (Final image above), the very first Messier Object to be discovered by Charles Messier himself in 1764.  Consisting of 500,000 stars, between 8 and 11-billion years old and spanning some 220 light-years, M3 is one of the largest and brightest (absolute) globular clusters associated with the Milky Way – about 300,000 times brighter than our Sun.  It is noteworthy that the cluster contains some 274 variable stars, the highest number of any clusters, as well as a relatively high number of ‘blue stragglers’ – young main-sequence stars that appear to bluer and more luminous than the other stars in the cluster and are thought to be formed through stellar interaction of the older stars.

M3 LRGB Crop (Large)

With these attributes it is not surprising that M3 is considered a popular target in astrophotography (cropped image above), likely surpassed however by M13 AKA the Great Globular Cluster in Hercules (cropped image top-of-the-page), which conveniently follows M3 in the same area of the sky about 3-hours later (together with nearby the globular cluster M92).  And so having bagged M3 it was time to turn the telescope and camera towards M13 (Main image below).  Discovered by the eponymous Edmond Hailey in 1716 (he of Hailey’s Comet), seen from Earth M13 is slightly brighter than M3 with a wide range of star colours that certainly makes for an exciting image.  At 11.65 billion years old, M13 has been around almost three times as long as the planet Earth.

M13 LRGB Final (Large)

Since starting astrophotography I like to try my hand at imaging a globular cluster at least once each year but hitherto with disappointing results.  This time I’m pleased with the outcome, especially M13 which is surely one of the most magnificent objects in our night sky; as a bonus there are also a few galaxies in the background of both the M3 and M13 images too.  It is therefore fortunate that for those of us in the higher latitudes of the northern hemisphere the Great Globular Cluster in Hercules can be seen all-year round, though is at its highest and therefore best position between May and September – thereby inaccessible for the Kiwis who are instead compensated by Alpha Centauri!  I expect to be back again next year to marvel at these amazing and enigmatic objects, if not before.

M3 Location Crop

IMAGING DETAILS
Object M3    (NGC 5272)     
Constellation Canes Venatici
Distance 33.9 million light-years
Size 18.0’ or 220 light-years     
Apparent Magnitude +6.2
 
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 ZWO x 8 + ZWO LRGB & Ha- OIII-SII 7nm filters 
Capture & Processing Astro Photography Tool + PS2,  Deep Sky Stacker & Photoshop CS2
Image Location Centre  RA 13:42:23     DEC 28:22:50  
Exposures 24 x 180 sec L + 10×180 sec RGB  (Total time: 162 minutes)   
  Unity @ 139 Gain   21  Offset @ -20oC    
Calibration 10 x 180sec Darks  20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 5th + 6th  May 2018 @ +23.00h

M13 Location Crop

IMAGING DETAILS
Object M13     (NGC 6205)
Constellation Hercules
Distance >=20,000 light-years
Size 20’  or 150 light-years
Apparent Magnitude +5.8
 
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
Image Location Centre  RA 12:39:59    DEC -11:37:20  
Exposures 20 x 180 sec L + 15×180 sec RGB  (Total time: 195 minutes)   
  @ Unity 139 Gain   21  Offset @ -20oC  USB 40 
Calibration 10 x 180sec Darks  20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 6th + 7th + 9th May 2018 @ +00.30h  

 

Chapeau!

LRGB GxC Crop-2 (Large)

 

I always had a general interest in astronomy but was eventually sparked into action after viewing Saturn through the Thompson 26 inch refractor at Herstmonceaux observatory in 2014.  The beauty of the planet and its unique rings is captivating and like many others it remains my favourite planet to this day.  One year on and looking further afield at Joan Genebriera’s Tacande Observatory on the island of La Palma, I discovered what is now  one of my very favourite Deep Sky Objects – M104 or the Sombrero Galaxy; until recently I used the resulting picture obtained whilst at La Palma as the main banner image for this website.  Though perhaps not as spectacular as the Orion Nebula or certain spiral galaxies, the sombrero-like galaxy (with a passing resemblance of a flying saucer too), is beguiling in its own unique way and ever since then I’ve been eager to return to The Hat and image it myself from home.

Chart_1.cdc3

However, imaging the Sombrero from the UK and especially at my location just south of London is quite another matter to La Palma.  Aside from light pollution, being at 51o north compared to 28o in La Palma, M104 is considerably lower in the sky when viewed from Fairvale Observatory in Redhill; at the time of imaging in early May it was about 26o above the southern horizon.  Furthermore, my sight lines are obscured on three sides by 15-foot hedges and directly south by two 45-foot conifers – see below SE to SW view of M104 imaging track at Fairvale Observatory.

M104 Track crop

As a result, only after it emerges from behind the western edge of the aforesaid conifers can M104 (just) be imaged, as it moves along the top of the hedge for just over an hour before disappearing from view once again.  Of course this is far from ideal but with my enthusiasm for the Sombrero, a high-resolution ZWO1600M-Cool camera and newly acquired ability to plate solve, I gave it a try over three consecutive nights.

 

RGB GxC crop (Large)

 

An unbarred spiral galaxy, the hallmark of M104 is its bright bulbous centre encircled by dark dust lanes, which when viewed from Earth tilted at just 6-degrees above the equatorial plane creates the appearance of a sombrero hat (see cropped image above).  With the much higher resolution of the Hubble telescope some 2,000 globular clusters have been identified with M104, ten-times that of the Milky Way.  In 1912 the galaxy was found to be moving away from Earth at 700 miles per second, providing an early indication that the Universe was in fact expanding in all directions.

All-in-all the Sombrero galaxy is a fascinating and unusual object, though small and all-in-all a challenging imaging target, especially seen from Fairvale Observatory.  Notwithstanding, at last I am very pleased to obtain my own exciting image of the Sombrero – chapeau!

M104 Location

IMAGING DETAILS
Object Sombrero Galaxy  M104     
Constellation Virgo
Distance 29 million light-years
Size 9’ x 4’  or  50,000 light-years
Apparent Magnitude +8.0
 
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera ZWO1600MM-Cool (mono)   CMOS sensor
  FOV 2.65o x 2.0o Resolution 2.05”/pix  Max. image size 4,656 x 3,520 pix   
EFW ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters 
Capture & Processing Astro Photography Tool + PS2,  Deep Sky Stacker & Photoshop CS2
Image Position Centre  RA 12:39:59    DEC -11:37:20  
Exposures 25 x 180 sec L + 3x5x180 sec RGB  (Total time: 120 minutes)   
  @ 139 Gain   21  Offset @ -20oC    
Calibration 10 x 180sec Darks  20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 5h + 6th + 7th  May 2018 @ 23.30h  approx.

 

 

Spinning Plates

65 Comp Lgx Crop

Much of life is about meeting and dealing with challenges. Who hasn’t put off a task in the hope either that it will go away, somebody else will deal with it or an easier solution might be found?  Whatever anybody says to the contrary, astrophotography is not easy and throws up many such challenges from the very beginning, which will usually have to be dealt with if progress is to be made.  Amongst such challenges a few have the potential to transform the process and / or outcome of imaging but can also irrationally at first appear as a stumbling block rather than an opportunity and, as a result, get put aside until another day.

My list of such obstacles so far confronted consists of:

I have experienced many other challenges but excluding processing itself – which is another story – overcoming these four tasks has each time had a material positive impact on my astrophotography.

It’s fair to say that with technology, problems and life in general, wherever possible I like to adopt the KISS principle (Keep It Simple Stupid).  Unfortunately such a philosophy is often difficult, if not impossible to follow with astrophotography and most of the time there is just no alternative but to work through the unavoidable difficulties step-by-step in every excruciating detail, which usually requires lots of patience, perseverance and time.  In understanding and finding a solution the almost endless and invaluable online help from others should not be overlooked, without which I would probably still be back at the proverbial square one.  The availability of such friendly help and the extensive free but still excellent software is surely one of the defining characteristics of astronomy and astrophotography, which not only makes it easier but more enjoyable.

Notwithstanding, when I look back at the aforementioned list of tasks which took me months or even years to address and solve, I wonder now why I had been so daunted beforehand.  Once I found the courage to work through the problems, I discovered that I too was able to set-up and carry out such techniques that hitherto I’d thought beyond my abilities.  It was very satisfying but, more to the point, each such breakthrough took me to another level of imaging.

Ever since moving on from DSLR to using the ZWO1600mm-Cool mono camera and EFW, I realised that if I was ever going to truly master astrophotography I would need to achieve much longer integration times, which could only mean one thing – the apparently black art of plate solving.  I had read about plate solving and understood the principle but at first was too busy learning the new camera and then either just kept putting it off or, with so much bad weather, used the rare clear night just to enjoy imaging.  Notwithstanding, an all too brief warm and clear spell recently occurred and I decided to give it a try.

Aside from the innate underlying complexity of such techniques I am first put off by the instructions. I do read them but as always with technical items they appear to have been written by an alien – poorly written, idiosyncratic and altogether difficult to understand.  In this case I chose to use PlaneWave’s PlateSolve2 software incorporated within the excellent image capture software Astro Photography Tool (APT) as Point Craft and to be fair, the author’s (Ivo from Hungary) instructions are comprehensive but still difficult to understand; thankfully the related APT Forum helps enormously to resolve resulting difficulties and misunderstandings. However, like riding a bike you will not learn by reading a book but need to get on and do it!

Having installed the necessary software and star catalogues for plate solving my first night was for various reasons a disaster, thankfully the good weather continued for the subsequent two evenings and I was therefore able to continue.  To learn the technique I needed a suitable target and at this time of the year the Leo Triplet formed an easily recognisable composition that met the bill, though the detail of each galaxy remains difficult to resolve with my set-up.  My approach was first to verify I could Solve an image i.e. identify the exact RA and DEC position of the image (location and orientation) using the plate solving software and then using this image and solved data:

  1. Re-position the camera exactly over the target in the same part of the sky
  2. Do the same but after a Meridian flip, and finally…
  3. Do the same using the original image but over two nights
PoinCraft

APT PointCraft input screen: After connecting the scope, solving the image (upper box) and framing the image (lower box), the GoTo++ function can be used to return the scope and imaging location to the originally solved and framed position in order to resume imaging.

I’m not going to say I’ve cracked it but I did achieve all the above tasks and am now confident that I’m on my way to obtaining longer integration times with the help of plate solving.  After some failures I was finally able to realign the camera to within 2 pixels, which is quite amazing accuracy achieved by the software.   I was even pleased with the resulting test images, which however emphasised the aforementioned need for much greater integration times; top-of-the page image from separate image sets on 19th April, image below from image sets on 20th April.  Of course increased times will also require clear skies and a return to more suitable targets.

Picture saved with settings embedded.Despite my aversion towards much of the so-called modern world I am not a technophobe, I embrace and often enjoy many of today’s technical developments.  However, I am of the opinion that many of the problems with such technology arise at the interface between the technology and mankind – technology is now (mostly) digital and we are analogue i.e. incompatible. Furthermore, such difficulties are often compounded by the lack of intuitive operation and inability of those creating such devices or software to explain to normal human beings how to use them – surely altogether a limiting factor for the ultimate development of the modern world itself? Notwithstanding and somewhat ironically, my experience indicates astrophotography may also be a metaphor for life.  Often working in the unknown, difficult, complex and frustrating but at times very rewarding – a bit like spinning plates really? And so on to my next plate – watch this space!

Leo

IMAGING DETAILS
Object The Leo Triplet   M65 + M66 + NGC 3628     
Constellation Leo
Distance 35 million light-years
Size M65 8.7’ x 2.45’      M66 9.1’ x4.2’      NGC 3628  15.1’ x 3.6’
Apparent Magnitude M65 +10.25              M66 + 8.9             NGC 3628  + 10.2
 
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
Image Location Centre  RA 11:19:59    DEC 13:31:01  
Exposures 1.Main image  60 sec x35* LRGB  (Total time: 100 minutes)  *15 East & 10 West

2. Second image  180 sec x 5 LRGB (Total time: 60 minutes)

  @ 300 Gain  50  Offset @ -20oC    
Calibration 1.   15 x 60 sec Darks  20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU 25,000  

2.   10 x 60 sec Darks  20 x 1/4000 sec Bias  10 x Flats LRGB  @ ADU25,000

Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 19th & 20th February 2018 @ 22.00h approx.

Playing With Fire

RGB (Large)

When possible my current repertoire has continued with DSO targets previously imaged with a modded DSLR and now revisited using the ZWO1600MM-Cool camera.  In general I’ve found the outcome with the new camera has been noticeably better in detail and colour but I’m still learning and know I can do better in time.  Last imaged in December 2015 with a DSRL camera, the larger FOV comfortably encompassed both the Tadpole (IC410) and adjacent Flaming Star (IC405) nebulae, resulting in an exciting composition. However, this time the ZWO CMOS sensor could only accommodate the latter in the image but with improved resolution.

fn3

Picture saved with settings embedded.

IC 405 (right) The Flaming Star Nebula & IC 410 The Tadpole Nebula: WO GT81 & modded Canon 550D + FF | 15 x 180 sec @ ISO 1,600 & full calibration | 8th December 2015

The Flaming Star is an emission / reflection nebula, which surrounds the bright blue variable star AE Aurigae.  Imaging in narrowband produced decent Ha data but was very weak in OIII and SII wavelengths and even with 2-hours integration time is somewhat lacking in colour both in SHO (top-of-the-page) & HOO (below).  Notwithstanding, it’s an exciting object that at some point in the future will obviously require much longer imaging time and perhaps even a mosaic  in order to include its neighbour the Tadpole once again.

HOO (Large)

FN

IMAGING DETAILS
Object The Flaming Star Nebula   IC405     
Constellation Auriga
Distance 1,500 light-years
Size 37’ x 19’  
Apparent Magnitude +6.0
 
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera ZWO1600MM-Cool (mono)   CMOS sensor
  FOV 2.65o x 2.0o Resolution 2.05”/pix  Max. image size 4,656 x 3,520 pix   
EFW ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters 
Capture & Processing Astro Photography Tool,  Deep Sky Stacker & Photoshop CS2
Exposures 300 sec x12 Ha, x6 SII & x6 OIII (Total time: 120 minutes)
  @ 139 Gain  21 Offset @ -20oC  
Calibration 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x Flats Ha, OIII & SII @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 24th February 2018 @ 20.30h approx.

 

Lost In Space

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Night produces a very different feeling to day.  Familiar locations take on a distinct atmosphere created by the absence of light, as the darkness imbues a sense of being in another world.  With restricted sight other senses of sound, temperature and smell become more vivid.  Furthermore, as my familiarity with the night sky has improved through astronomy, I’ve felt an increasing impression of physical separation.  Just being outside at 3.0 a.m. in the morning when most others are in bed, one becomes not only more aware of the night’s unique senses but a magical feeling of Earth’s movement through space itself.

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  The Milky Way & Magellanic Clouds from Slab Hut Creek, South Island, New Zealand 

When travelling I like to read and learn about the new places I visit, in order to gain insight into the people, their culture, what’s happening and what makes them tick.  For this purpose during my recent trip to New Zealand I enjoyed reading two very different but equally fascinating books:

  • Long Cloud Ride by Josie Dew, which describes Josie Dew’s epic 6,000 mile cycle journey around New Zealand, and…
  • Squashed Possums by Jonathan Tindale. ‘Written’ by a caravan (that’s right!) assisted by its occupant. Possums describes life off the beaten track in New Zealand, specifically Jon’s life in a semi-derelict caravan in the wilderness.  The experience provides an amusing but insightful description of New Zealand, New Zealanders and the impact of living in such a remote location on humankind.  Apart from the practical and physical issues, the impact is sometimes profound – for the caravan and Jon – I was particularly struck by the description of their experience of the night sky in the back country, which powerfully captures something of my own feelings of being outside on a clear night, alone in the darkness.

SQP

I put my book down, pulled not one but two jumpers on and ventured outside to look at the cloudless night sky.  Brrr! True, it was cold, freezing probably but the view was breathtaking.  The Moon was out, or at least some of it was, and the Milky Way stretched across the sky like a colossal halo embracing the planet.  The Southern Cross stood proud, forever pointing north (?).  I turned around to look at my caravan, its windows filled with light, surrounded by the stars and darkness, reminding me of a satellite.  Lost and far away, suspended in space, I imagined an astronomer observe me from afar.

I stood there a while, quietly watching and taking in the view.  I tasted the chilled air, with a sense of time winding down a gear.  The there was a palpable jolt, like a quite earthquake that left no physical impression.  There was no crack in the earth, but there had been a change nonetheless – a profound and intoxicating sensation.

For a moment, I was disconnected.  I felt strangely without form, somehow insubstantial and insignificant.  Lost, like a speck on a rock in the darkness.  At least it might have been a moment, it may well have been much longer.  Moments may have been minutes, minutes might have been hours.  Time ceased to have any meaning.

I’d stumbled across something that is not easy to express.  It was the feeling of utter isolation, of removal not just from society, but from the world and then finally being removed from my own sense of self.  And yet, something intangible was filling this void and it pushed a tickle up my spine.

The sense of isolation quickly dissipated and instead of feeling lost, I had the profound experience of being part of everything – the earth, air and stars – all of it.  I was utterly overwhelmed by this new awareness. My subconscious struggled desperately to find a cultural reference point to cling to.  David Bowman swam past, cast adrift in the final moments of 2001: Space Odyssey, calling out to Bowie’s Major Tom.

And then, as quickly as it happened, the moment passed.  I was returned to reality, with something like an elastic twang. I’d not so much been thrown but catapulted back to this small patch of damp grass on a cold night, having been in an unexplained place.  What on earth was that?  One thing I was sure of, I was desperate for a steaming hot mug of tea.

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Hive Of Activity

 

M44 Crop (Large)

Identified by Ptolemy in the second century AD, the open star cluster was known in Greek and Roman mythology as Praesepe (The Manger). Soon after developing the so-called ‘Dutch Gadget’ for use in astronomy as a refractor in 1609, Galileo became the first person to properly observe through the telescope what is now known as The Beehive Cluster and thus detect some 40 stars.  In 1769 Messier added the cluster to his growing catalogue as the 44th object and thus became M44.  More than 400 years since Galileo’s first view, the Beehive Cluster AKA M44, Praesepe or more prosaically NGC 2632, is now known to consist of approximately 1,000 stars and forms one of the imaging targets at or about the time of the Spring Equinox each year.

M44 Locate

Located in our galaxy relatively nearby within the constellation Cancer, between 520 and 610 light-years away and 3-times the Moon’s diameter or 1.5o, The Beehive can be seen with the naked eye as a blur in dark skies and with a telescope becomes an excellent imaging target.  Last imaged with the modded Canon 550D DSLR in 2015, the LRGB image obtained this time shows improvement but with only 20-minutes integration time lacks the colour seen in other examples, which however consist of more than 17 hours! Truth is that this was a brief experiment carried out between imaging two other objects on the same night and I’m encouraged that by increasing my time significantly I can eventually tease out better quality and the spectacular colours that make The Beehive such an attractive open cluster.

IMAGING DETAILS
Object The Beehive Nebula   (Praesepe, M44, NGC 2632)     
Constellation Cancer
Distance 520 – 610 light-years
Size 1.5o  
Apparent Magnitude +3.7
 
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera ZWO1600MM-Cool (mono)   CMOS sensor
  FOV 2.65o x 2.0o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix   
EFW ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters 
Capture & Processing Astro Photography Tool,  Deep Sky Stacker & Photoshop CS2
Exposures 4×5 x 60 sec LRGB (Total time: 20 minutes)
  @ 139 Gain  21 Offset @ -20oC  
Calibration 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x Flats Ha, OIII & SII @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 11th February 2018 @ 21.30h approx.

 

Death Throes of a Star

Abell 21 RGB 1Final (Large)

As the winter arm of the Milky Way proceeds inexorably towards the west, I’ve been seeking new objects and was pleasantly surprised to recently discover a small but nonetheless interesting planetary nebula located just to the east of the galactic plane between Canis Minor and Gemini.  Consisting of large filaments of glowing ionized gas, the feature goes by the popular name of the Medusa Nebula, after the Greek mythological gorgon figure which has hair of writhing snakes!

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Statue of Medusa

Also known as Abell 21 (discovered by George Abell in 1955), Medusa is an ancient planetary nebula some 1,500 light-years away, officially situated within the constellation Gemini.  Like its dramatic mythological namesake, the planetary nebula represents the final stages of a low mass star such as our sun in the process of transforming from a red giant to hot a white dwarf star, in the process shedding its outer layers which are illuminated by ultraviolet radiation from the hot star within which powers its glow.

Medusa

At 4-light years across the Medusa Nebula is a small though reasonable size but with an apparent magnitude of some +15.99 is very faint and is therefore difficult to image.  Nonetheless, Ha and OIII gases are prevalent and as something of an experiment I chose to try and image this object at narrowband wavelenghts.

Abell 21 RGB 1FinalCrop (Large)

Considering the aforesaid problems I am quite pleased with the outcome (top of page), indeed I was surprised to see I had captured anything.  However, given its challenging low brightness and a total integration time of only 75-minutes, the final image was always going to be lacking in detail and noisy (cropped image immediately above).  Notwithstanding, now I know of its presence I will surely be returning to The Medusa Nebula on another occasion to improve the integration time and perhaps use a larger telescope to grab those photons which prove elusive to my current equipment set-up.

 

IMAGING DETAILS
Object The Medusa Nebula    (Abell 21 / Sharpless 2-274)     
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
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera ZWO1600MM-Cool (mono)   CMOS sensor
  FOV 2.65o x 2.0o    Resolution 2.05”/pix  Max. image size 4,656 x 3,520 pix   
EFW ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters 
Capture & Processing Astro Photography Tool,  Deep Sky Stacker & Photoshop CS2
Exposures 10 x 300 sec Ha, 5 x 300 sec  OIII   (Total time: 75 minutes)
  @ 139 Gain  21 Offset @ -20oC  
Calibration 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x Flats Ha, OIII & SII @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 11th February 2018 @ 23.00h approx.

 

The Fox & Cone

Cone Ha100 20 15 OIII B CROP

After the fun of December and January provided by the wide choice of exciting DSO objects, February affords a worthy finale to the winter season, in particular within the constellation Monoceros.  After successfully imaging the Rosette Nebula on 9th February, a few days later I was able to move on to another nearby HII-region in the Milky Way, with equally good results.  Surprisingly it’s been just over 3-years since I last imaged the same part of the sky just before Christmas 2014, on that occasion with an unmodded Cannon 700D DSLR.  Now armed with the more capable ZWO1600MM-Cool camera and narrowband filters, the potential for raising the bar was good and the results did not disappoint.

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Of foremost interest this time was NGC 2264, which officially describes the Cone Nebula and Christmas Tree Cluster but also includes the Snowflake Cluster and Fox Fur Nebula, all set within a large HII-region.  Individually each object is towards the limit of my equipment’s resolution but taken all together makes for an interesting combination when encompassed inside the 2.65o x 2.00o field-of-view.  Like the Rosette I chose to image in narrowband, with a total integration time of 90 minutes; again using 300 second subs at Unity gain proved to be very effective – I suspect that only more subs rather than longer exposures would lead to a better outcome but that will have to wait until I’ve sorted how to plate solve, watch this space!

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I’ve recently been experimenting in Photoshop using star masks and related sharpening and contrast enhancement methods, which for the first time I applied when processing these images to great effect.   Being an HII-region the overall image area is dominated by Ha-light and the processed Ha-subs resulted in a very exciting image at this wavelength, with many subtleties revealed throughout (see below).  On the other hand OIII and especially SII wavelengths are much less prevalent, from which it would seem  that a higher ratio of those subs would be required to better tease out detail at those wavelengths.  Notwithstanding, the resulting Ha-OIII-OIII Bi-Colour image has turned out well (top of the page), with all the aforementioned objects showing clearly.

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The signature object of this image is probably the Cone Nebula.  New stars are forming within a cone shaped dark molecular cloud, itself sculpted by strong stellar winds. However, I consider the Fox Fur Nebula (Sharpless-273) to be the bigger imaging challenge, which I’m therefore pleased to say is starting to show well in these images.  The name derives from the rich, fur-like texture of the nebula which is also shaped by stellar winds; reckon The Fox & Cone would make a good pub name! Below:  Cone Nebula & Christmas Tree Cluster Ha-OIII-OIII before colour mapping.

Cone Ha100 20 15 OIII A crop

But there’s more. A series of stars form an inverted outline shape of the so-called Christmas Tree Cluster above the Cone Nebula (see image above), with the conspicuously bright 15 Monocerotis at its base made of a massive variable star system.  And finally, somewhat off piste, lurking in the top right corner of the main image is NGC 2261 or Hubble’s Variable Nebula.  Discovered by Edwin Hubble in 1949, the nebula is illuminated by the unseen R Monocerotis star and forms a small but distinct bright triangular area.

All-in-all this is a great part of the February sky for imaging.  There’s still more to discover and I won’t leave it as long as 3-years before going back again, with the objectives of increasing integration time and possible addition of RGB subs to enhance the colour potential.

IMAGING DETAILS
Object Fox  & Cone Nebulae  NGC 2264 + Hubble’s Variable Nebula NGC  2261     
Constellation Monoceros
Distance 2,700 light-years
Size Approx. 54’ x 37’
Apparent Magnitude +3.9
 
Scope  William Optics GT81 + Focal Reducer FL 382mm  f4.72
Mount SW AZ-EQ6 GT + EQASCOM computer control
Guiding William Optics 50mm guide scope
  + Starlight Xpress Lodestar X2 guide camera & PHD2 control
Camera ZWO1600MM-Cool (mono)   CMOS sensor
  FOV 2.65o x 2.0o    Resolution 2.05”/pix   Max. image size 4,656 x 3,520 pix   
EFW ZWOx8 + ZWO LRGB & Ha OIII SII 7nm filters 
Capture & Processing Astro Photography Tool,  Deep Sky Stacker & Photoshop CS2
Exposures 12 x 300 sec Ha, 6 x 300 sec  OIII   (Total time: 90 minutes)
  @ 139 Gain  21 Offset @ -20oC  
Calibration 5 x 300 sec Darks  20 x 1/4000 sec Bias  10 x Flats Ha, OIII & SII @ ADU 25,000  
Location & Darkness Fairvale Observatory – Redhill – Surrey – UK        Typically Bortle 5
Date & Time 11th February 2018 @ 21.00h