This image of IC 410 - the emission nebula surrounding open cluster NGC 1893 in the constellation of Auriga, the charioteer - was Picture of the Month in the June 2013 issue of Astronomy Now magazine. To say I was delighted is an understatement.
This is a narrowband image using Ha, [OIII], and [SII] filters to produce a false colour image using the Hubble palette. The image was made by digitally stacking 600 second exposures: 24 for the Ha, 22 for the [OIII], and 21 of the [SII] for a total integration time of 11 hours and 10 minutes. The data was captured in January, February, and March 2013 using an Atik 460ex CCD camera. The [OIII] and [SII] was captured with a Takahashi FSQ-85 and the Ha a combination of the Takahashi and a TS90APO. I used a Celestron CG-5 mount. The individual images were registered using RegiStar, stacked using Deep Sky Stacker, and processed in PhotoShop CS2.
IC 410 the Tadpoles - Astronomy Now, June 2013
The Triangulum Galaxy is the third largest in our local group of galaxies. Unlike most other galaxies visible from Earth, M33 has quite a large angular size in the sky of about a degree - roughly the width of two full moons - and therefore filled the frame of an Atik 460ex quite nicely using my TS90APO refractor.
The luminance for this image is a combination of 30 x 600 second and 4 x 1200 second subframes and the colour from a modest 5 x 600s frames for red, 3 x 600s for green, and 3 x 900s for blue. These were stacked in AstroArt 5, processed with Serif PhotoPlus X4.
If I am perfectly honest I was never very happy with this image (it has a horrible gradient which I have corrected in the version in my Messier objects section), but I was very, very happy that Sky at Night Magazine thought it good enough to publish in the ‘hotshots’ section of the May 2013 issue; my first published image!
M33 the Triangulum Galaxy - Sky at Night Magazine, May 2013
This image is of M51, the stunning Whirlpool Galaxy in the constellation Canes Venatici, the hunting dogs. M51 is made up of two interacting galaxies, NGC 5194 and NGC 5195, the latter being ripped apart by the gravitational pull of its larger companion sending material streaming between them.
The data capture for this image was a labour of love: I collected almost 10 hours of luminance data in 300 second sub-frames in April, May, and June 2013. Following advice in Sky at Night Magazine I added RGB with 25 subs for each channel using 100 second exposures for Red, 125 seconds for Green, and 150 seconds for Blue, all binned 3x3. The data didn’t actually require too much processing, just a bit of high pass sharpening and I was amazed at the vibrancy of the colours.
M51 the Whirlpool Galaxy - Sky at Night Magazine, September 2013
I had a productive time hunting galaxies over the summer of 2013 and was very pleased that two of the resulting images got published - this one of M81, Bode’s Nebula, in the October issue of Astronomy Now.
I used pretty much the same approach for this as I did for the Whirlpool Galaxy (M51), taking a lot of time and effort over the luminance and getting away with a light touch on the RGB which, as for M51, was binned 3x3. However, the colour on this image was a real challenge to bring out; it is nowhere near as vibrant as the Whirlpool and the RGB took a lot of careful processing (and a number of attempts).
I captured 5 hours of luminance for this image with about an hour more for each of the RGB channels. I was really pleased that this image got a half page in the magazine but the printed image made me realize that the stars are actually a bit soft; I was concentrating on the core of the galaxy and getting detail in the dust lanes and wish now that I had done more to tighten up the stars.
M81 Bode’s Nebula - Astronomy Now, October 2013
Completely surprised to open my copy of Sky at Night Magazine and see this image peering back at me; I had no idea it was going to be included. This is a narrowband rendition of the Elephant’s Trunk Nebula in Cepheus using the familiar Hubble Palette.
My first attempt at processing this data was underwhelming to say the least and I had trouble getting a good colour balance. So I used a new (to me) workflow for this - an iteration of Joel Short’s workflow which meant I blended 20% of the Ha signal in to both the [OIII] and [SII]. I was pleased with the results including the reasonably natural looking star colours (though of course this is a false colour image). The Ha signal is so strong that I used it as a luminance layer at full strength.
This image has about 12 hours of data… and I had to restart the Ha as I wasn’t happy with the framing of the first attempt so spent plenty of time on data acquisition for this one!
IC 1396 the Elephant’s Trunk Nebula - Sky at Night Magazine, November 2013
My count in Sky at Night Magazine reached five with this image of M27 the Dumbbell Nebula in Vulpecula, the little fox. It is a planetary nebula consisting of huge clouds of glowing gas that has been blown off by a star that exploded about 15,000 years ago. In addition to all that glowing gas, the remnant of the explosion is now a White Dwarf star of about the same mass as our sun, but that is only the size of the Earth. The nebula is about 1.5 light years across and lies about 1,360 light years away.
I had imaged this target before but in October 2013, with my longer focal-length guiding working a little better, I decided to give it another go. This is just two hours’ worth of data - an hour each through hydrogen-alpha and oxygen III filters. With a relatively small amount of data I was delighted to capture the outer halo, though I did deliberately change the colour mapping to make use of orange and light blue instead of the more familiar red and navy which helped to lift the halo out of the background sky. You can just about see it in the printed magazine!
M27 the Dumbbell Nebula - Sky at Night Magazine, February 2014
So I must confess to feeling ever so slightly disappointed that this image of the Bubble Nebula in the constellation Cassiopeia only made it on to the cover disc of the January 2014 edition of Sky at Night Magazine rather than in print. Perhaps I’m getting a bit greedy, but this is one of my favourite targets and I think it’s also one of my best images.
There are 14 hours of hard-won data here at a pretty long focal length so the data acquisition was a challenge. It’s another narrowband image and I’d originally processed the data using the Hubble palette but was unhappy that the nebulosity behind the bubble was an unpleasant brown and so this version uses the Canada France Hawaii Telescope scheme which to me gives a much more pleasing result.
NCG 7635 the Bubble Nebula - Sky at Night Magazine (cover disc), January 2014
This was one of the only targets I was able to image in the first part of 2014 so I was particularly pleased that it was published in Astronomy Now. The Jellyfish Nebula is a supernova remnant - the remains of a star that exploded - located about 5,000 light years from Earth in the constellation of Gemini.
This is an HaRGB image where the glowing hydrogen gas that dominates the nebula is picked out using a hydrogen alpha (Ha) filter and used to augment a colour image made up from separate data captured through red, green, and blue filters. The advantage of this approach is that it gives natural star colours.
I spent more time processing this image than any other I’ve done as controlling Propus (the red star to the right of the image) was an absolute nightmare!
IC 443 / Sh2-248 the Jellyfish Nebula - Astronomy Now, June 2014
I really like this bi-colour image of the Rosette Nebula in the constellation of Monoceros, the Unicorn, as it has a really dynamic, fiery quality to it. This has 10 hours worth of data - 15 1200s exposures for Hydrogen alpha and the same amount of [OIII]. It’s a stunning object and emits strongly in both of these emission bands. It is therefore a popular target for amateur astroimagers.
The nebula is thought to lie about 5,200 light years from Earth and is around 130 light years in diameter. It is an object that is absolutely packed full of interesting details including a number of Bok Globules - dark clouds of dense cosmic dust and gas. In the Rosette Nebula, a number of these form the shapes of animals including a leaping puma, a donkey, a dog, and a turtle…
The image was included on the cover disc of the June 2014 issue of Sky at Night Magazine.
NGC 2237 / Caldwell 49 the Rosette Nebula - Sky at Night Magazine (cover disc), June 2014
This image was first light for my new iOptron CEM60-EC mount. The Sunflower Galaxy lies about 37 million light years away from us which means that the light recorded here started its journey to my back garden 37 million years ago (during the Priabonian age of the Paleogene period here on Earth - gosh!)
This was taken with my EdgeHD telescope at it’s native focal length of 2800mm. I’d never managed acceptable results at this focal length with my other mount despite a lot of fettling so to get this image first time out was very pleasing - doubly-so that Astronomy Now chose to publish it.
There isn’t a huge amount of data here - just 16 x 300s luminance un-binned, and 8 x 180s each of RGB, binned 2x2 for a total integration time of 2.5 hours (not much for me…)
M63 the Sunflower Galaxy - Astronomy Now, August 2014
I was really using the wrong telescope for this picture of M101 the Pinwheel Galaxy in Ursa Major, the Great Bear. It’s pretty big with an apparent angular size of 29 arcminutes and therefore doesn’t quite fit in the frame. In any case it’s an object that in my view looks better with some space around it (pun intended).
In addition, the poor UK weather limited the amount of data I could capture - 7 x 300s of luminance, 12 x 180s of RGB and 5 x 300s of Ha to enhance the star forming regions. It could really do with a lot more data as the background sky is pretty blotchy. The image was included on the cover disc of the September 2014 issue of Sky at Night Magazine, but doesn’t look brilliant, I am afraid.
Nonetheless I was really pleased with the detail in the galaxy, although I had some tilt in my imaging train and so the stars in the upper left needed some work.
M101 the Pinwheel Galaxy - Sky at Night Magazine (cover disc), September 2014
So as far as Sky at Night Magazine goes this is three straight on the cover disc as opposed to in the printed magazine which is disappointing in a sense but given the volume of images submitted I am actually pleased to have the images picked up at all…
In fact the first three completed images using my new CEM60-EC mount all got published, so that’s got to be good, right?! This is also my twelfth published image - enough for a calendar!
This is the Cocoon Nebula - an emission / reflection nebula in the constellation of Cygnus the swan. The image comprises 28 five minute subs in the red channel and 24 five minute subs in each of the green and blue for a total integration time of just over 6 hours.
Caldwell 19 / IC 5146 the Cocoon Nebula - Sky at Night Magazine (cover disc), November 2014
This was my second attempt at capturing our close neighbour - the Andromeda Galaxy. I often spend several nights on a single target but such was the poor weather that this image was captured on one night in October 2014. It is a straightforward RGB image taken with 3 minute sub-exposures - 18 each of red, green, and blue for a total integration time of just 2.7 hours - but it is a relatively bright target so came out quite well.
Another picture of M31 appeared as Picture of the Month in Sky at Night Magazine shortly after I’d submitted this image so I figured that I’d missed out on the chance of publication . I was therefore really surprised to see my M31 in the February issue of the magazine.
When capturing this data I was testing a new focal reducer on my Takahashi FSQ-85 so very pleased to get a published image out of it.
M31 the Andromeda Galaxy - Sky at Night Magazine, February 2015