This month’s imaging object is a single star shot – this time I’ve gone for Regulus in Leo.  A nice bright star central to an image can make a spectacular picture, and Regulus is no exception.  Taken using the Sky 90 and M25C with 4-minute subs and a couple of hours total exposure time, this is the sort of result you can expect.  However – what I didn’t expect was to see a trace of the dwarf galaxy Leo 1, which looks like a tiny wisp of a cloud right next door to Regulus!  This was pretty much unexpected and I believe it is due to the superb contrast provided by the Sky 90 – I can guarantee that I wouldn’t be able to see Leo 1 in a similar Hyperstar III image.  It would be interesting to know whether you can pick up Leo 1 using reflectors and CCD cameras with Regulus providing it’s own unique form of  ”light pollution” in this region.

Recipe for a Regulus/Leo 1 image – good dark (Moonless) night, high contrast imager (refractor), moderate length subs, but lots of them – and possibly some good luck

Until April’s IOM – clear skies!

I still find it very strange that this large, bright reflection nebula does not have a “popular” name.  To me it look like a cauldron of boiling liquid oxygen, so I shall call it “the Cauldron”.  M78 is a beautiful reflection nebula in Orion, and you can see from the accompanying image that it lies very close to Barnard’s Loop.  As you will know, Barnard’s Loop is faint, so to get this showing up in the image it is a good idea to collect some narrowband H-alpha data.  The reflection nebula although appearing to be narrowband blue is in fact broadband blue (due to scattering of a broad band of short wavelengths of light) – so M78 doe not benefit from narrowband filters.  However, you can see that the whole area is also permeated by dark dust clouds, and to get these showing up at all in your image you need lots of exposure time and long subs.  This image is a composite of H-alpha data taken with the Sky90/M25C, RGB data of M78 alone taken with the original Hyperstar and SXV-H9C, and finally the main part of the template is Hyperstar III RGB data with its 2.41 x 1.6 degree field of view.  You can see that by framing the subject (M78) off to the right of the FOV you can bring in the edge of Barnard’s Loop over to the left which makes for a more interesting image.

Usual formula for a nice picture – lots of subs – long exposure time for each sub – and add some good deep H-alpha data to capture the faint Barnard’s Loop.  At least we still have long nights to do this stuff, soon the clocks will go forward and it will be back to no imaging before 9:00 p.m.

Clear skies until our March edition of IOM.

First of all Happy New Year to you all!  I won’t say let’s hope for better imaging weather this coming year as so far it hasn’t been anything to write home about.  Moving on.  This month’s Imaging Object of the Month is the beautiful Jellyfish nebula in Gemini.  This is a very difficult time of the year for imagers as there is so much up there in a good imaging position right now, including all the stuff in Auriga and of course Orion and Monoceros.  IC443 is pretty faint and does well with the addition of narrowband data to the RGB, especially H-alpha and S-II.  IC443 is also BIG – you can see from the accompanying image that the rather large FOV of the Sky 90/M25C combination (2.22 x 3.33 degrees) is just about perfect for the region.

This image took a LOT of work.  This is 3 hours of RGB, 9 hours and 40-minutes of H-alpha, and 3 hours and 40-minutes of  SII giving a total exposure time of 16 hours and 20-minutes – and it could have easily done with the same again!!  So the message is, lots of time, add narrowband – and perhaps make this your winter mega-project if you can manage to keep away from Orion

Clear skies until February!

Well, not exactly the Douglas Adam’s cluster as that would look like the number  ”42″ – whereas this open cluster in Orion bears a striking resemblance to the number “37″ and is therefore known as the 37-cluster.

The 37 cluster, NGC2169 lies around 3,000 light-years away in the constellation Orion.  Being a fairly bright open cluster we can get away with short 2-3 minute subs, and we can also get away with a short total imaging time of just a couple of hours.  You get a lot more back for your short investment in time than with many other deep-sky objects.  A little digital processing on your data (Noel’s enhance star colours helps a lot here) and you will end up with an incredible figure  ”37″ appearing like a Neon display in an otherwise unimpressive star background.

Just a short amount of time needed to bag this one – so you can move onto the many other gems of Orion in the same evening and grab some more data

See you again in the New Year, have a good Christmas, and let’s hope that 2010 brings us some better imaging weather than we got dished up in 2009!!

Our long dark evenings now mean we can start early and easily get a good 6-hours on an object – weather of course permitting.  This Month’s object will do well with 6 or more hours total imaging time on it – it is the Gamma Cassiopeia region of Cassiopeia.  I am particularly fond of the Cassiopeia region anyway for its incredible star fields – not only is it in a rich Milky Way region of space, but it is also jam-packed full of open clusters and it is very hard to take an image anywhere within Cassiopeia and not find that you’ve bagged an open cluster (or two).

Gamma Cass is special however, in that it has two faint, but very beautiful nebulae associated with it – namely IC59 and IC63.  These emission/reflection nebulae almost half-encircle Gamma Cass and the subtle red/blue hues creates a beautiful image with the surrounding Milky Way star field.  Being very faint this region needs both long sub-exposure times and a long total exposure time as well.  Even with the Hyperstar III at f#2 I used 10-minute sub-exposures, and for a low-noise final image it would be good to get around 60 subs (at least) meaning a time investment around 10-hours or so.  Not only do I have a single frame (deep) image of Gamma Cass with IC59 & IC63 – but there is also a 4-frame mosaic of the region awaiting Noel’s time – now that one will be a stunner!!  Needless to say with such a faint object you need optimum conditions – and that of course means no Moon.

Put in the time and effort on this one and you will be amply rewarded.

We are fast approaching my favourite imaging Month of the year  See you all again in December!

We are now enjoying long dark evenings and are once again getting into the swing of imaging well into the early hours – weather permitting.  The imaging object I have chosen for this month is the famous Double Cluster in the constellation Perseus.  The Double Cluster as the name suggests is made up from two beautiful open clusters, NGC 869 and NGC 884.  Walter Scott Houston in his Deep-Sky Wonders book has this down as a January object, but I find I have to have a go at looking/imaging this one the second it comes into a favourable position in my skies.  The usual description of this amazing object, when viewed through a low-power eyepiece is “Diamonds on Black-Velvet” – and I clearly recall my first observation of the Double Cluster throught the C11 was precisely just like that.  It is an incredible sight, and it is even a naked eye object appearing as a fuzzy glowing region near Cassiopeia.  In fact it is such an amazing visual object that CCD images rarely do it justice for reasons that will become apparent as we carry on examining this region.

If you use a low powered telescope, or better still a pair of 10 x 50 binoculars to look in the Double Cluster region, something very odd immediately strikes you.  Like ornaments on a charm bracelet the Double Cluster sits on the edge of a bright ring of stars which leap out at you when viewed through binoculars.  Now look at this region on a star map or planetarium program.  Although you can make out the ring of stars that make up “Greg’s Charm Bracelet” – they are by no means conspicuous, and don’t show themselves to be clearly differentiated in any way from the myriad of background stars in the region.  So this is clearly some sort of subtle eye-brain processing going on which makes the “Bracelet” so very clear when visually observed.  There are plenty more asterisms that “pop out” when observed through binoculars, but effectively “hide away” when looked at on planetarium programs and star maps – Kemble’s Cascade immediately comes to mind.  I think it is similar subtle processing by the brain-eye system that makes the Double Cluster itself so very striking.

Returning to imaging the Double Cluster, it is a matter of getting a large number of subs at maybe 2 or 3 minutes per sub, under Moonless conditions.  We can of course image clusters with the Moon up, but if we are trying to get that “Diamonds on Black Velvet” image, then we want the darkest skies possible.  It is also worth going as deep as possible as well in order to pull out the impressive dark rift that runs between the two clusters adding further to the  contrast when viewing this region.  For a nice noise-free image it is worth trying for at least 100 sub-exposures which means spending up to maybe 5-hours imaging the Double Cluster.  If you end up with an image that even approximates the view of the real thing – then it’s 5-hours really well spent.

Clear, dark skies until November’s object of the Month

At last!  September has come around again and we can actually start imaging before 10:00 p.m. hooray!!  Less baggy eyes at work the next morning   This Month’s imaging object is the mysterious-looking NGC7023, a reflection nebula known as the Iris nebula in the constellation Cepheus.  From my notes I started imaging this one around 9:45 p.m. so not that much before 10:00 p.m. but sufficiently early in the evening for it not to feel too painful.

You need to go deep on this one in order to do justice to all the dark nebulosity that surrounds the Iris.  Look carefully and you’ll see a huge “clover-leaf” pattern surrounding the Iris nebula where most of the stars are missing – this is the massive dark nebulosity that fills this region.  In order to get that rich brown colour that is often associated with dark nebulae you need to go deep, and that means 5-10 minute sub exposures with the Hyperstar and 10-20 minute subs with an f#4.5 instrument like a Sky 90.  For total exposure times you’d like to get around 4-6 hours with the Hyperstar which translates to in excess of 24-hours with the Sky 90, which is bordering on silly.  This example shows the power of Hyperstar imaging where you can download quality data 6 times faster than is possible with a very popular imaging refractor.

The Iris nebula lies at a distance of 1,400 light years in Cepheus, and it’s not an easy one to process as the core is so bright it is hard to control it and not having it “blow out”, while at the same time trying to show the dark nebulosity at its best.  You’ll know you’ve got quality (deep) data and that you’re processing is top-notch if you manage to bring out the little pink region lying very close to the core of the Iris.

Hooray!!  The earlier evenings have returned – we now have (hopefully) another 7 months of great imaging ahead of us.

I wish you clear, dark, Moonless September skies.

It’s still late starts for imaging during most of August, but beginning to get reasonable again for those of us that have to go along to the day job next morning.  This Month’s object is a beautiful region of (blue) reflection nebulosity in a sea of red (emission nebulosity) that is the Gamma Cygni region of Cygnus.  Surrounding the central star Sadr in Cygnus is a truly massive region of emission nebulosity, which can appear a little boring with its uniform red appearance.  However, towards the North of this region we hit a little blue gem that breaks up the monotonous red – and this is the reflection nebula NGC6914.

My notes say that I started imaging this one around 10:30 p.m. so that’s not too late to start grabbing data, but it is an object needing around 4 hours total with the Hyperstar and preferably in excess of 12 hours with something like an f#4.5 instrument.  Sub-exposure times of at least 5-minutes with the Hyperstar and at least 10-minutes with the Sky 90 are recommended.  Get in enough quality data and you’ll be rewarded by one of the prettiest images you’ll find in an emission nebula.

Wishing you clear August skies – not long to go now for those darker, earlier nights

This Month’s imaging object is a rather beautiful globular cluster in the constellation Sagitta – M71.  The nice bright star towards the top left in the image below is Gamma Sagitta, and M71 lies mid way between Gamma and Delta Sagitta.  M71 looks rather loose for a globular cluster and there was controversy over whether this object was in fact an open cluster – it seems without doubt that this is a globular cluster lying around 13,000 light years away in the constellation Sagitta.  I see from my notes that I did not start imaging this one until around 11:30 p.m. so we still have the problem of the late nights and early mornings of Summer   However, being a cluster we can keep the subs down to a reasonable 2 or 3 minutes each using either the f#2 Hyperstar or the f#4.5 Sky 90 which means that we don’t need to continue imaging until the Sun comes up, but we can get away with just a couple of hours or so of good data.

It is still a very difficult month for imaging with the very late starts, but after no imaging at all during the whole of June it’s now worth getting out to try and grab hold of ANYTHING.  I am now longing for the shorter evenings which start to make their appearance beyond mid-August.

Wishing you good weather and clear skies for this July

As per usual – I do not image during June as not only are the nights too short, but also it never really gets dark enough to be able to take good quality images.  However, having said that, I might just break my rule this year as we have had such a terrible start to the year weather-wise.

June is a month to thoroughly vacuum out the obsevatory and dust everything down.  Make sure all your backup batteries are fully charged and your telescope optics are nice and clean.  If you have a permanent observatory computer, bring it indoors (unless you have an outdoor Internet link) and get all the software and security updates loaded up.   Also (lightly) vacuum the air inlets of the computer if they appear dusty.  Does the observatory sealing round the base need attention, and do the dome rotation or sliding roof wheels need oiling and cleaning??  Does your fibreglass dome need a good car wash to remove the fine green film of algae, or does your shed-observatory need a fresh coat of preservative.

Now is the month to get all those niggling jobs done that you consistently put off for the other 11 months.  I won’t wish you clear skies as that will simply add to the frustration of this month – instead I wish you happy cleaning and upgrading.