2023 The Year In Pictures

January 1, 2024 by grahamrob in Broadband, Dark Nebula, Deep Sky Objects, Equipment, Galaxy, General Astronomy, Globular Cluster, Imaging, Mosaic, Narrowband, Nebula, Other, Planetary Nebula, Processing, Samyang 135, Supernova, Widefield Imaging and tagged Aurora Borealis, DSO Imaging, Galaxies, Nebulae | Leave a comment

This Christmas marks the 10^th edition of my astrophotography calendar, consisting of my better images from the previous 12-months, which I produce for myself and members of the family. Wow doesn’t time fly? Based on these images, I also compile a video of the images set to music, which we all watch together before seeing the actual calendar. It’s become something of an occasion and is a great way to present the images, which look wonderful on today’s smart TV’s and is fun to watch and share with the family.

THE CALENDAR

Much longer imaging times (total of more than 145 hours), re-imaging old favourites in new ways and unusual, overlooked, or difficult objects, resulted in a very good 2023 astrophotography year and perhaps the best calendar yet? The calendar for 2024 on YouTube can be viewed by clicking HERE and below is a brief overview of each image. More detailed background information and imaging details for those interested can be found in relevant blogs I posted on this website. The background music is the track Appleshine from Underworld’s album Drift.

COVER	SH2-284: Close-up of April’s image – along the inside of the ring structure are many dark dust pillars and globules, which on the right seem to resemble a hand with a bony finger pointing inwards!
JANUARY	NGC 1333: Nestled within the western area of the Perseus Molecular Cloud, some 1,100 light-years from Earth is the colourful NGC 1333 reflection nebula, one of the closest and most active star-forming regions of the night-sky.
FEBRUARY	Spaghetti Nebula: Straddling the boundary of Taurus and Auriga constellations, is the giant supernova remnant (SNR) Simeis-147. The stellar explosion occurred 40,000 years ago, leaving a rapidly spinning neutron star or pulsar at the core of the now complex and the expanding SNR.
MARCH	Aurora Borealis: Situated just below the Arctic Circle, Iceland is well known both for its geology and views of the Aurora Borealis, which we saw in March on the south coast near Kirkjubaejarkklaustur.
APRIL	SH2-284: A star-forming region of dust and gases, sculpted by radiation and interstellar winds emanating from a young (3 to 4 million years) star cluster located near the centre.
MAY	M3 Globular Cluster*: Consisting of 500,000 stars and over 11 billion years old, M3 is one of150 globular clusters that orbit around the Milky Way Galaxy.
JUNE	*M27 Apple Core Nebula:** A planetary nebula, consisting of a glowing shell of ionized gas ejected from a red giant star in its late stage of life to become a white dwarf. Complex hydrogen (red) and oxygen (blue) fans form around the outer regions, with a pulsar-like beam transecting the nebula.
JULY	Monkey Head Nebula: Located 6,400 light years from Earth in the Orion constellation, the ‘Monkey’ is a so-called emission nebula, where new stars are being created within at a rapid rate.
AUGUST	SH2-115: This widefield image contains a richness of various emission nebulae, centred around the distinctive large blue SH2-115 region. Just to the left of SH2-115 is the small but enigmatic SH2-116 a faint, blue disc thought to be a planetary nebula.
SEPTEMBER	LDN-768 Black Cat Nebula: Close to M27 in the constellation of Vulpecula (“Little Fox”), is a dense region of stars broken-up by dark nebulae to create intriguing shapes. Here strung out from left-to-right, several of the dark nebulae seem to coalesce (visually) to create the form of a black cat.
OCTOBER		SH2-126 Great Lacerta Nebula: On the western edge of the Milky Way in the southern part of Lacerta, is the very large but faint emission nebula SH2-126. The red filament structures stretch over 3 degrees, to the right is the Gecko Nebula, a molecular cloud associated with bright young stars.
NOVEMBER		Flaming Star & Tadpoles Nebula: Two emission nebulae: dust & gas of the Flaming Star (below) combined with red ionized hydrogen gas produces a flame affect. Above, the stellar winds and radiation pressure from hot massive stars creates the Tadpoles ‘wriggling’ away from the centre.
DECEMBER		*M51 Whirlpool Galaxy:** As the smaller galaxy passes behind M51, joint gravitational forces are interacting, resulting in the misalignment of stars and unusually bright blue and pink areas across the Whirlpool galaxy. Their fates are inextricably linked and might eventually merge.
*Footnote:* All images taken from Redhill, Surrey or telescope at a dark sky site in New Mexico, USA shown by an asterisk*
*HAPPY NEW YEAR + CLEAR SKIES FOR 2024*

Supernova Sensation

February 6, 2023 by grahamrob in Deep Sky Objects, Equipment, Imaging, Narrowband, Samyang 135, SNR, Supernova, Widefield Imaging and tagged Auriga | 2 Comments

Straddling the boundary of Taurus and Auriga, is the giant supernova remnant (SNR) Simeis-147 AKA SH2-240 or the Spaghetti Nebula. It is believed that the stellar explosion that created Simeis-147 occurred some 40,000 years ago, leaving behind a rapidly spinning neutron star or pulsar at the core of the now complex, expanding SNR; the nebulous area has an almost spherical shell consisting of numerous filamentary structures. With an apparent diameter of 3^othe SNR spans some 160 light-years, making it a very large astrophotography target.

I’ve long admired the spectacular SNR Simeis-147 AKA Spaghetti Nebula, which I first imaged with my standard William Optics GT81 scope in January 2022. The outcome (see image below) was pleasing but with the limited FOV it had to be just a nibble of this large object – something of an appetiser you might say. Therefore, ever since putting my Samyang rig together last summer I’ve had only one object in mind with this excellent widefield set-up, which had to be the full menu version of Simeis-147!

Apart from its size, Simeis-147 is very faint, making long exposure time essential, which is always difficult in the UK. However, a rare spell of cold, clear nights this January provided sufficient opportunity over five nights to obtain just over 20-hours integration and a complete image of this truly magnificent SNR.

Notwithstanding the favourable conditions and long-time achieved – a record for me at this location – the faint nature of this object made image processing difficult too. After experimenting, I eventually adopted a tone mapping technique: pre-processing each individual wavelength stack before removing the stars, stretching and processing each of the starless Ha and OIII images before combining using Pixel Math in the ratio: R – (Ha*1.70) + G – (OIII*0.80)+(Ha*0.20) + B- (OIII*0.80)+(Ha*0.20).

With further processing of the HOO starless combination I was able to obtain the desired result of marvellous SNR detail, together with pleasing Ha (red) and especially OIII (blue/green) colours, that altogether with the addition of the stars and some final tweaking produced a striking image with good depth. Moreover, I feel the widefield setting achieved using the Samyang 135 lens produces a striking setting for this fascinating object.

	IMAGING DETAILS
Object	Simeis 147 / SH2-240 AKA Spaghetti Nebula
Constellation	Taurus
Distance	3,000 light-years
Size	Approx. 3.0^o
Apparent Magnitude	Extremely faint

Scope / Lens	Samyang 135 @f2.8
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	Sky-Watcher EvoGuide 50ED
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 7.5^o x 5.67^o Resolution 5.81”/pix Max. Image Size 4,656 x 3,520 pix
EFW	ZWOx8 EFW & 31mm ZWO LRGB & 7nm Narrowband filters
Capture & Processing	Astro Photography Tool + PHD2 + PixInsight v1.8.9-1
Image Location & Orientation	Centre: RA 05:41:15.081 DEC +28:05:32.778 Right = North Top = East
Exposures	60 x 600 sec Ha, 62 x 600 sec OIII Total Integration Time: 20 hr 20 min
	@ 139 Gain 21 Offset @ -15^oC
Calibration	5 x 600 sec Darks 20 x Flats & Flat Darks
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5 – 6
Date & Time	12^th 17^th 18^th 19^th & 21^st January 2023 @ +18.30h
Weather	Approx. <=0^oC RH >=80% 🌙 70% to 0^o New Moon

A New Perspective

August 19, 2022 by grahamrob in Deep Sky Objects, Equipment, General Astronomy, Imaging, Narrowband, Supernova, Widefield Imaging and tagged Cygnus, DSO Imaging | 2 Comments

It’s been nearly two years since acquiring my Samyang 135 lens but since then it’s unfortunately only had limited use in combination with my modded 550D DSLR. Whilst impressed with the results from this set-up, my main objective has always been to combine it with my ASI1600 mono camera for some serious widefield astrophotography but as that was being used with my William Optics refractor it just didn’t happen, until now. After upgrading to a ASI294MM Pro camera in May, at last I was finally able spend the early part of this summer working on a new Samyang 135 + ASI1600 rig and now that astronomical darkness is (just) back I recently managed to catch a few photons with this new set-up of the large SNR Cygnus Loop.

I originally purchased a x2-ring Astrokraken 3D-printed clamping system for the lens + DSLR combination from Philippe in France but since then he’s tweaked the design. In particular x3 built-in M4 nuts have been incorporated on either side of each of the two main lens clamping rings, for the purpose of attaching ancillary equipment, which for me has been a game changer. I therefore bought a new x3-ring Astrokraken bracket, with the said bolt holes, around which to build my new rig:

The two main clamping rings that hold the lens have a shoe immediately above the lens, to which I’ve fitted a Sky-Watcher EvoGuide 50ED guidescope (not yet working), with the rear third ring holding the ASI1600 mono camera & EFW.
I swapped the Canon lens bayonet adapter for a bespoke M42 screw adapter, in order to ensure a more secure attachment, thus reducing any potential lens-camera movement at this critical point of the image train.
I’m continuing to use the excellent Astrokraken micro-focuser, which consists of a ring that clamps onto to the lens’ focus ring, with two small bolts above that make contact with either side of the guidescope shoe, so that when turned the focus ring can be adjusted either way to obtain focus, which is then locked when completed. So far I’ve found the micro-focuser to work very well with this lens, assisted by the addition of an Astrokraken Bahtinov mask which is inserted into the front of the lens casing.
Using this lens with the ZWO ASI1600MM-Cool camera and EFW, the backfocus guideline is 44mm, which I was able to achieve by adding an Altair T2 variable locking extension ring set to 17.5mm = 44mm minus 26.5 (camera + EFW).
With my Chroma filters now being used with the new ASI294MM Pro camera, I purchased another ZWO 31mm x8 EFW and brought my ZWO 31mm filters out of retirement.
Finally, using the new M4 nut holes I’ve added a Baader Skysurfer III RDF on the left-hand side of the Astrokraken bracket system to help with sky navigation and framing.

After bolting the Astrokraken with the lens, camera and said components to a Losmandy plate it makes a very nice compact rig, that is easy to handle and store. Notwithstanding, as they say – the proof of the pudding is in the eating: SEE top-of-the page for original image & below for 50% crop.

Whilst the recent heatwave produced clear skies, it was far from ideal here for astronomy and was further hampered by a full moon. However, with only just over two hours integration time and a few Dark calibration files, I’m still impressed with the outcome of this quite amazing lens. It is very pleasing to capture the entire Cygnus Loop comfortably sitting within the lens’ FOV – for information on this FOV and comparisons go to this previous WTSM blog HERE. For me context is important with astrophotography and in this regard the astronomical perspective this lens produces is outstanding, no wonder it is so popular. I just love working with this FOV and can’t wait for better conditions for greater integration time and more widefield targets to point this wicked little lens at.

	IMAGING DETAILS
Object	Cygnus Loop
Constellation	Cygnus
Distance	2,400 light-years
Size	3.0^o
Apparent Magnitude	+7.0

Scope / Lens	Samyang 135 @f2.8
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding – Not Used	Sky-Watcher EvoGuide 50ED
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 7.5^o x 5.67^o Resolution 5.81”/pix Max. Image Size 4,656 x 3,520 pix
EFW	ZWOx8 EFW & 31mm ZWO LRGB & 7nm Narrowband filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker, PixInsight v1.8.8-12, Photoshop CC, Topaz Denoise
Image Location & Orientation	Centre RA 20:52:28.01 DEC +31:14:56.186 Right = North Top = East
Exposures	27 x 180 sec Ha, 20 x 180 sec OIII Total Integration Time: 4hr 21 min
	@ 139 Gain 21 Offset @ -10^oC
Calibration	5 x 180 sec Darks
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	9^th & 10^h August 2022 @ +22.00h
Weather	Approx. 27^oC RH <=50% 🌙 96% Full Moon

Cosmic Spaghetti

January 25, 2022 by grahamrob in Deep Sky Objects, General Astronomy, Imaging, Narrowband, Supernova and tagged Taurus Constellation | 1 Comment

Long on my to-do list has been the spectacular Simeis 147, also known as SH2-240 or the Spaghetti Nebula. A large supernova remnant (SNR) spanning the border between the Taurus and Auriga constellations, which despite its size is one of the faintest objects in the night sky and therefore not an easy astrophotography target. Moreover, given my equipment’s field-of-view the large size of the SNR would require a mosaic to fully image, which is generally out of the question here at Fairvale Observatory with the limited clear sky conditions that prevail here. Therefore, for the moment I’ve concentrated on a close-up area of the southern lobe, imaged and processed in HOO narrowband to highlight the beautiful complexity of this cosmic cataclysm that is the product of a massive stellar explosion that took place some 40,000 years ago.

Furthermore, imaging was not helped by the presence of a waning full moon and even with 10-minute exposures, only very limited detail was evident in the Ha wavelength and none in OIII, thus also making framing tricky. However, with over 12-hours integration time eventually obtained over four nights and very careful processing, my first image of this wonderful SNR does not disappoint. I hope to return to this magnificent object again in the future to add more exposures – you really cannot have too many – and perhaps eventually capture this bowl of cosmic spaghetti in its entirety one day too.

	IMAGING DETAILS
Object	Simeis 147 AKA SH2-240 or Spaghetti Nebula
Constellation	Taurus
Distance	3,000 light-years
Size	Total object +3.0^o
Apparent Magnitude	Extemely faint

Scope	William Optics GT81 + Focal Reducer FL 382mm f4.72
Mount	SW AZ-EQ6 GT + EQASCOM computer control & Cartes du Ciel
Guiding	William Optics 50mm guide scope
	+ Starlight Xpress Lodestar X2 camera & PHD2 guiding
Camera	ZWO1600MM-Cool mono CMOS sensor
	FOV 2.65^o x 2.0^o Resolution 2.05”/pix Max. image size 4,656 x 3,520 pix
EFW	ZWOx8 EFW & 31mm Chroma 3nm Ha, OPIII & SII filters
Capture & Processing	Astro Photography Tool + PHD2 + Deep Sky Stacker, PixInsight v1.8.8-12, Photoshop CC, Topaz AI Denoise
Image Location & Orientation	Centre RA 05:41:28.486 DEC +28:01:51.616 Left = North Top = West
Exposures	39 x 10 min Ha, 34 x 10 min & 9 x 10 min SII Total Integration Time: 12 hr 10 min
	@ 139 Gain 21 Offset @ -20^oC
Calibration	5 x 10 min Darks, 15 x Ha, OIII, SII flats and Flat Darks @ ADU 25,000
Location & Darkness	Fairvale Observatory – Redhill – Surrey – UK Typically Bortle 5-6
Date & Time	21^st December 2021 + 4^th, 5^th & 6^th January 2022 @ +19.00h
Weather	Approx. <2^oC RH >=80% 🌙 96% → 21%

2021 The Year In Pictures

January 1, 2022 by grahamrob in AstroBin, Broadband, Dark Nebula, Deep Sky Objects, Galaxy, General Astronomy, Globular Cluster, Imaging, Narrowband, Nebula, Processing, Star Cluster, Supernova, Widefield Imaging and tagged Astrophotography, DSO Imaging | Leave a comment

Every year since 2014 I’ve published a retrospective blog of my astrophotgraphy year just ending called Reflections. It’s been a useful task that enables me to bring together the best and sometimes the worst of my images, in order to consider the good and bad points + progress made + set some objectives for the coming year. Eight years on, after which I believe I’ve now reached at least a respectable level of imaging and processing, I’ve decided to stop this format for the time being.

Notwithstanding, at this time of the year I also produce an astrophotography calendar for members of my family, which consists of the better images from the year just ending; I think they like them and certainly all use the calendar during the coming year. Moreover, I also recently started to compile a video of the said calendar images set to appropriate music, which we all watch together prior to seeing the actual calendar. It’s a great way to present the images, which look really stunning on today’s large Smart TV’s and is fun to watch with the family too.

The video for this last year 2021 can be viewed on YouTube HERE and below is a brief very general overview of each image. More detailed background information and imaging details for those interested can be found in relevant blogs posted on this site during the past year.

2022 CALENDAR

A new set of filters, improved processing techniques and access to data from a telescope at a dark sky site in New Mexico, USA (shown by an asterisk *) contributed to an exciting astrophotography year in 2021.

FRONT COVER	The Carnival of Animals: Special processing of the inner region of the Rosette Nebula highlights the ‘animals’ or Bok Globules – clouds of dust undergoing gravitational collapse as part of the process of new star formation.
JANUARY	LDN-1250 Dark Nebula*: Dark or absorption nebulae are a type of interstellar cloud which are so dense they obscure or absorb visible light emitted from objects behind or within and thereby contrast with the general light flux of the Universe as dark areas.
FEBRUARY	CTB-1 Supernova Remnant*: The overall structure of this supernova remnant is that of a circular shell, with a conspicuous rupture towards the north (lower right of image). The main red Ha-shell is composed of multiple interlocking filament limbs, with a blue / green OIII arc along one side.
MARCH	Jellyfish Nebula: Locatedin the Gemini constellation some 5,000 light years from Earth, this is a remnant of a supernova that took place during the past 30,000 years. With a diameter of 70 light-years, the object is visually speaking nearly twice the size of a full moon.
APRIL	Markarian’s Chain: The Virgo cluster consists of more than 2,000 galaxies, within which Markarian’s Chain forms a J-curve string of bright galaxies that share a common motion through space.
MAY	*M13 Great Globular Cluster of Hercules:** Consisting of several hundred thousand stars and 145 light-years in diameter, M13 is considered to be the finest cluster in the Northern Hemisphere.
JUNE	*Cave Nebula**: Located along the plane of the Milky Way is the diffuse emission nebula referred to as the Cave Nebula. The Cave at the centre is critically located at the boundary of the Cepheus molecular cloud and the hot, young stars which ionize the surrounding gases to great effect.
JULY	Orion Widefield: Framed around the area of Orion’s Belt, the Horsehead Nebula and the Great Orion Nebula, look hard and the refection nebula M78 can also be seen in the lower left corner.
AUGUST	*Elephant’s Trunk Nebula**: A very large emission nebula, the so-called Elephant’s Trunk Nebula is rightly viewed as one of astrophotography’s most iconic images. The ‘trunk’ itself dominates the centre of this image and is illuminated from behind by a bright star forming region.
SEPTEMBER	M31 Andromeda Galaxy: The full benefit of new filters, improved guiding, clear skies over 6-nights and extensive use of new processing techniques can be seen in my best image yet of Andromeda.
OCTOBER	Butterfly Nebula: Situatedwithin the Orion Arm of the Milky Way is the Gamma Cygni nebula, a diffuse emission nebula surrounding the star Sadr. Either side of the dark rift which divides the image from top to bottom are two large bright areas that together form the so-called Butterfly.
NOVEMBER	M33 Triangulum Galaxy: Like it’s neighbour Andromeda, better data and processing has produced an exciting new image of M33 this year, the red areas highlight Ha-rich star-forming regions
DECEMBER	Flying Bat & Giant Squid Nebula*: This very faint OIII emission nebula Ou4 required an imaging time of 40-hours. For obvious reasons Ou4 has become known as the Giant Squid Nebula which, moreover, lies within the much larger SH2-129 HII emission region or the Flying Bat Nebula.

HAPPY NEW YEAR + CLEAR SKIES IN 2022

Cosmic Eruption

July 30, 2021 by grahamrob in General Astronomy, Imaging, Narrowband, Supernova and tagged Cassiopeia, DSO Imaging | Leave a comment

Originally thought to be a planetary nebula, Abell included this object in his catalogue as Abell-85 but later in 1971 it was revised as a supernova remnant (SNR) and renamed CTB-1, thus also denoting it as a radio source. The overall structure is a circular shell with a conspicuous rupture towards the north (bottom right of image). The main red Ha-shell is composed of multiple interlocking filament limbs, with a blue / green OIII arc along one side (see main image above).

I experimented extensively processing the data because of its overall complexity and is an interesting object, which is therfore also presented below as greyscale Ha-wavelength only and starless versions. The main Ha and OIII data is shot at long 1,800 second exposures, which together with RGB adds up to a whopping 29 hours of integration time. However, CTB-1 is an extremely faint object, which probably still requires considerably more time – I’ve seen somebody else’s 61-hour integration which they described as “not enough” and despite the quality of their image I’d probably have to agree.

CTB-1 is a very exciting object, which might have been what Douglas Adams had in mind when creating Milliways or The Restaurant At The End Of The Universe in the Hitchhiker’s Guide, from which such spectacular events could be ordered to view with your meal!

	IMAGING DETAILS
Object	CTB-1 (Abell-85)
Constellation	Cassiopeia
Distance	10,000 light-years
Size	35 arcminutes ~ 100 light-years
Apparent Magnitude	–

Scope	Takahashi FSQ 106 FL 530mm f/5 + Moonlight Nightcrawler focuser
Mount	Paramount MyT
Guiding	Yes
Camera	QSI 683-WSG8 KAF-8300 full frame CCD sensor 5.4nm pixels
	FOV 1.94^o x 1.46^o Resolution 2.1”/pix. Image array 3326 x 2,507 pix
Processing	Deep Sky Stacker, PixInsight v1.8.8-8, Photoshop CS3
Image Location & Orientation	Centre – RA 23:59:19.402 DEC +62:25:39.406 North = bottom right
Exposures	29 Ha & 20 OIII x 1,800 secs @ -15C 18 R 17 G 19 B x 300 secs Total Integration Time: 29hr
Calibration	48 x 1,800 secs Darks* x47 Bias & x16 HaOIII +LRGB Flats *RGB scaled to 300sec
Location & Darkness	Deep Sky West – amateur hosting facility near Rowe, New Mexico – USA SQM Typically >= 21.7
Date & Time	Q3 2020