First off the Cocoon.

I’m finally happy with this image, the dust clouds which have so long evaded me and now there and the dark nebula is really standing out.

I applied the same technique changes ot the Cave as well:

And again the improvement in clear to me, much more depth and contrast in the fainter areas. Now all I need is a clear night on a weekend without a bright moon so that maybe I can take something new!

Anyway, lets see what I have been up to.

NGC7380 – The Wizard or Flying Horse Nebula

43×5 minutes (215 minutes total)
250mm F4.8 Reflector
Canon 1000D (Modified)

A challenging object from my light polluted garden and really it begs for a better camera to really get the most out of it. I’ve been playng with this image in Pixinsight using some new tools in an attempt to get more out of it so there may be another reprocessing post at some point.

Caldwell 9 – The Cave Nebula

50×6 minutes (300 minutes total)
250mm f4.8 Reflector
Canon 1000D (Modified)

This came out much better than expected, and is a great region for imaging. This is also the image which saw my long running guiding issues with the CGEM finally sorted, which basically meant ignoring every bit of advice on the Yahoo CGEM users group and doing exactly as the PHD instructions recommend. No backlash correction, only guide in one direction on DEC and use a well trained PEC curve.

NGC7129 & NGC7142

58×6 minutes (348 minutes total)
250mm f4.8 Reflector
Canon 1000D (Modified)

NGC7129 is the reflection nebula,NGC7142 is the open cluster on the right.

Ngc7129 doesn’t appear to have a special name of it’s own, though I’ve heard it described as looking like a rosebud, personally I see a light bulb, with the orange glow of the edge of the bubble inside the blue reflection region being the filament. Reflection nebula, especially ones this faint are a real pig for me to process, I really didn’t expect to much form this to be honest. Although it’s not spectacular I’m happy enough with the end result.

Jupiter

Click on the images to see the animation

I spent a night testing out the OpticStar PL-131C camera as a planetary and lunar camera. I have been using it for guiding since August and for that purpose it is at least reasonable, though the sensitivity is a bit low so it does force you to hunt around for good guide stars. However I had hopes that it would make for a decent planetary camera, or at least an improvement over the modified webcam.

This animation is made up of around one and a half hours of data, a mixed bag of frames depending on the seeing but a nice result.

The same data, keeping those image in which Io was visible.

This is one of the videos which make up a single frame of the animations, the seeing was pretty good that night, very stable. I do need to invest in a 5x Barlow at some point though.

The Moon

My last image is a six frame mosaic of the moon taken with the Pl-131c through my 250mm F4.8 reflector at prime focus. To see this in it’s full glory I’d suggest clicking here to view the full sized image.

So that’s it for the last few months, hopefully now my leg is improving I’ll be able to get back to it, though the first thing I need to be doing is rearranging the shed to move the desk area to the door end so I have space to work. I’ll be doing that this weekend

I’ve also been refreshing my memory on the correct use of HDR Wavelet Transform, ACDNR, DBE for images without much background and Colour Calibration. Putting that all together I have taken a second look at three recent images to see what comes out of the other end.

The Elephant’s Trunk  Nebula I think came out the best, showing cleaner detail, better colour and contrast and a more uniform background.

My Cygnus Core image also shows great improvement I think, though I may have let a small green tinge in whilst dialling back the red. However overall I think it’s a solid step forward.

The Cocoon nebula once again, this image has become the bain of my life and even though this is a major improvement it’s still not where I want it to be. Faint dust clouds seem to be a problem for either my location, equipment or processing skills, I’m just not sure which.

There is something to be said for makers of astronomy equipment taking up a method of connectivity which is actually to be found on modern computers. The inclusions of a standard ethernet port on the Vixen Sphinx is perfect. The iOptron IEQ45 mounts have USB connectivity as standard as well, so perhaps there is some movement towards this, a pity Celestron didn’t push further with the CGEM to make it stand out more from the EQ6 it is cloned from.

Anyway, hunting around for something to image I went back to my copy of The 100 Best Astrophotography Targets for inspiration and decided upon the Elephants Trunk nebula in the IC1396 region of Cepheus. I managed to grab a couple of hours on both nights, though some strong winds, annoying clouds and unwanted movement whilst imaging near the zenith caused a few lost frames.

• Canon 1000D (Modified)
• Astronomik CLS-CCD Filter
• Orion Optics 250mm f4.8 Reflector
• 29 x 5 minutes (21 x bias, dark and flat)

Needless to say though the roof box contained my Vixen Sphinx mount, my camera and a few telescopes most of which I did not make use of as I ended up finally taking out the Canon EF 50mm lens I bought over a year ago for astrophotography and making use of it for something other that pictures of the wife and kids.

The second week of our holiday saw the moon waning and provided the ideal nights, however the weather was changeable and though I spent two nights out only one gave a full evening of clear skies.

Cygnus Central Region

Cygnus was the target for the first night being well placed above me and offering a rich area for widefield imaging. I wanted to capture the North American and Sadr Butterfly nebula regions though I notice that the Cocoon makes an appearance as well in the bottom left. Many other objects are visibly and I think this one came out the best.

• 33 x 5 minutes (bias, flat and dark applied)

Cassiopeia

The second night saw intermittent cloud until midnight which then cleared till 3am. A very frustrating night and this region was not my actual target. However after the troubles trying to get something worth having from the Sagittarius / Scutum area it was a relief to use my last hour or so to quickly gather some data from this region. The framing is a bit out, it needs to rotate anti-clockwise about 20 degrees.

• 14 x 4 minutes (bias, flat and dark applied)

Sagittarius / Scutum

This was the region I really wanted to photograph and I was saving it for the best possible night, unfortunately the weather didn’t want to play. After being clear all day the clouds rolled in from the south west almost the minute I had everything setup and ready to go. A waiting game then commenced with me comfortable in the boot of the car on my inflatable mattress watching a movie and waiting to see what would happen. I knew that in order to get this region I needed to get started on it as early in the night as possible, so a cloud delay was not good news. As it happen the clouds did eventually clear just after midnight. Unfortunately this was just a little to late for me and allowed for only a few images to be captured before it sunk behind the trees. I’ll leave this as a target for another day.

• 9 x 5 minutes (bias, dark and flat applied)

The Cocoon itself is a combination or emission and reflection nebulosity, the dark nebula that stretchs out from it is a cloud of dense dust blocking out the light from the stars behind it.

Imaging Equipment

• William Optics ZS66SD
• William Optics MkII Field Flattener
• Canon EOS 1000D (modified)
• Astronomic CLS CCD Filter

Guiding and Mount

• Orion Optics 250mm F4.7 Reflector
• Opticstar PL-131C Camera
• IR/UV Cut Filter
• Celestron CGEM Mount
• PHD Guiding

Exposures

• 44 x 5 minutes
• 15 x bias
• 15 x dark
• 15 x flat

The images were calibrated, aligned, stacked and processed in Pixinsight.

With the processing of this image I took the opportunity to try some new processing techniques within Pixinsight with the aim of improving noise reduction and getting better colour from the image. You can see some of my other attempts from the NGC and Other Catalogs gallery page. The first image is from my standard technique which ended up with a poor colour balance, the second was better in that respect but suffered from noise issues especially in the regions of the dark nebula.

In the version shown on this page I used the following techniques to try and get a better result, the links will take you to the Pixinsight forum post which discusses them :

Wavelet-based noise reduction with the ATrousWaveletTransform tool

I have always used the ACDNR tool in Pixinsight before to manage noise reduction post histogram stretch / sharpening when the image is in a non-linear state. Noise reduction from this alternative newer method however can be applied to a linear image and works as many tools do in Pixinsight by working different structure size layers. This means your noise reduction can be tailored to match the level of noise you have, hopefully that way avoiding blotchy backgrounds where larger areas of noise have been let through as structure.

I was very happy with the result once I had spent some time on trial and error to achieve the best result for my image.

RGB Re-Combination using Linear Fit

Technically I am pretty sure this is not for us single shot colour DSLR imagers but I cannot complain at the result. The technique here is to do a rough stretch of your Luminance data (I used an extracted lightness image) that looks about right, then match that stretch on your RGB images before applying Linear Fit tool to the RGB to match them against a reference image. I still had to use the SCNR tool to remove excess green from the final image but I have to call myself happy with the end result. Colour seems easier to manage, and the red of the Cocoon is closer to red than my normal orange. It is not scientific and probably not right for my data but as an experiment into alternative processing I like the result.

Hopefully the wait between new images can be a bit shorted this time!

And the second one taken last night :

The problem with the first image was a thin haze in the air which was catching the light pollution, it does nothing for your imaging, washing away fainter details.

Anyway, with several clear night to choose from I started over from scratch on NGC2903, capturing 42 new images through evenings of good seeing throughout the week. I think the result shows clear improvement.

NGC2903 Barred Spiral Galaxy in Leo

• Pixel scale:1.83 arcsec/pixel
• Field size :30.55 x 21.20 arcminutes
• Field contains:
  • NGC 2903

Exposures

• 42 x 5 minutes
• 21 x bias
• 21 x dark
• 21 x flat

With a fully clear night last night and no plans for today I calculated that I could capture another hour on NGC2903 and leave myself four hours for a second target. After consulting my new copy of the excellent ‘100 Best Astrophotography Targets‘ by Ruben Kier I decided that NGC4565 looked like a suitable target, both due to it’s position in the sky which would allow the full four hours and for it’s apparent size. Guiding went smoothly throughout the night as did the meridian flip.

NGC4565 The Needle Galaxy in Coma Berenices

• Pixel scale:1.71 arcsec/pixel
• Field size :29.19 x 20.87 arcminutes
• Field contains:
  • NGC 4562
  • NGC 4565

Exposures

• 48 x 5 minutes
• 21 x bias
• 21 x dark
• 21 x flat

I have spent more time in Pixinsight on both images trying to get better colour from them, I think the results are good on that front. Normally I use an extracted lightness mask when performing the saturation stretch, but found in this case that it was actually masking off the fainter parts of NGC2903, improvements to that process allowed me to bring out the blue of the fainter spiral arms. A similar technique was used for NGC4565, there may be a better image still hiding in the data but for now I am happy with the results.

I reopened each of the stacked but unprocessed images in Pixinsight to have another go and see if I could work out what was going wrong. Previously I had improved my colour correction by ensuring that I did not normalize the image during the dynamic background extraction process, but I had been neglecting to make use of the colour calibration tool after this, trusting instead to the colour balance of the modified camera combined with the Astronomik CLS-CCD filter, plus some manual tweaks later on in the process.

This time round I went back to Harry’s excellent Pixinsight tutorials and combined the colour calibration lesson into my own process. It really does help to go back to fundamentals some times, a refresher for the brain to remind yourself why you are working in a specific way. The results can be seen below, I think compared to the original images posted here and elsewhere these versions show significant improvement. Most notably in the galaxies where the ‘nearby galaxy’ method of colour correction has done wonders.

NGC4244 – Significant improvement, obvious colouration in the centre of the galaxy, better star colours and better background.

NGC2403 – Shows greatly improved colour, areas of nebulosity are standing out very nicely now, though the image lacks some sharpness I think.

NGC2174 – Colour calibration was completed via the aggregated stars method, not such a massive change as seen in the images above but it is certainly improved. Greater contrast and range is visible.

We’re very much heading into galaxy season now, where the chance to image nebulas is replaced with the chance to image faint and often very small galaxies instead. At least small for my field of view, it does present a problem. Once I have imaged all the targets which fit nicely in my field of view, be they the very few single galaxies or the nice groups I am left chasing very tough, small targets which may give me a nice challenge but don’t give a particularly impressive photo at the end.

The other options of course is to go back over the better targets with improved equipment and more knowledge instead.

Anyway, this is NGC4244, an edge on loose spiral galaxy in the constellation Canes Venatici. The processing was tougher than normal, it took several revisions of my image integration settings to get a good result against the noise. Generally I’m quite happy with the result.

Imaging Equipment

• Orion Optics 250mm F4.7 Reflector
• Baader MPCC
• Canon EOS 1000D (modified)
• Astronomic CLS CCD Filter

Guiding and Mount

• William Optics ZS66SD
• LX Modified Philips SPC900NC Webcam
• IR/UV Cut Filter
• Celestron CGEM Mount
• Guidemaster Autoguiding software

Exposures

• 27 x 5 minutes
• 15 x bias
• 15 x dark
• 15 x flat

The images were calibrated, aligned, stacked and processed in Pixinsight.

Wow, nearly two months since my last update, that is pretty terrible, insert normal excuses about the weather here. Still we have had some clear nights and I have found the time to get out whilst taking the last of sleep hit in the morning and the first of my new images can bee seen below.

This object has been my target since mid January, but I have been constantly distracted by poor weather or equipment problems. The graphics card in the observatory PC appears to have failed on me, so I need to find a new one of those. Also the mount had shifted during recent modifications to the way I mount my telescopes which was badly effecting guiding. Not only that but I seem to have encountered a strange issue with the declination axis binding, where as guiding it appears to start rapidly moving off in one direction and it takes a few minutes to correct it back, where upon it will run perfectly smoothly for another five minutes or so before drifting off in the other direction. This is odd, we would expect declination to only drift off one way. Added to this is that I did not have this problem at all when imaging another object much higher up with the mount on the opposite side.

Anyway, the first image to come out of all this is NGC 2174, the Monkey Head Nebula. I have shown it in this orientation as that seems the popular way up, and it looks sort of like a neanderthal man more than a monkey. If you invert the image it looks like a chimp, so pick which one you prefer.

NGC2174 is an emission nebula located in the constellation of Orion, a short way north of Betelgeuse. It is getting a bit late in the year for me to image in this region as I have a large tree to the south west which tends to get in the way. Next year I would like to do a widefield image with the Canon 50mm lens of the Orion region.

This is the first HA emission nebula I have imaged since the modification of the camera, I’m quite please with the result for only 90 minutes of data!

Imaging Equipment

• Orion Optics 250mm F4.7 Reflector
• Baader MPCC
• Canon EOS 1000D (modified)
• Astronomic CLS CCD Filter

Guiding and Mount

• William Optics ZS66SD
• LX Modified Philips SPC900NC Webcam
• IR/UV Cut Filter
• Celestron CGEM Mount
• Guidemaster Autoguiding software

Exposures

• 18 x 5 minutes
• 15 x bias
• 15 x dark
• 15 x flat

The images were calibrated, aligned, stacked and processed in Pixinsight.