Proper DSO Imaging

February 26 2011
Well, the cloud departed last night and I finally had the chance to try some 'proper' DSO imaging. When I say proper I mean doing everything by the book and accurately.
Polar Alignment - Check;
MPPC - Check;
DSLR - Check;
Finder Guider - Check;
1 Star Alignment - Check, sort of. The scope was quite a way out and I needed to strip down the DSLR and use a wide EP to find the intended target.
Tonight I wanted to make sure that the subject was suitably framed, accurately focussed and all my kit was used to its fullest potential.
It would also be my first time guiding with my Atik Titan on my Finderguider using PHD. At this point I would like to say a big thanks to everyone at SGL for the wealth of knowledge which meant my guiding setup and calibration went with a breeze resulting in a rather flatish graph as below:

My finder guider was set up using an adapter piece supplied by Bern at Modern Astronomy. A nicely turned piece allowing the Atik to be screwed into the finder to the required depth to achieve focus.
Before guiding I wanted to ensure that my setup was accurately focussed on my target. To do this I used Icarus Camera control for Mac. My DSLR was switched to PC mode and a series of 2 sec exposures made tweaking the focus each time once. Icarus allows tethered shooting but does not currently support Bulb so it was a useful tool to check focus on my laptop screen.
After accurately focussing I turned to PHD. Calibration took a couple of minutes and I was soon guiding.
So, what shall I try first? Well I plumped for a 600 second expisure firing my DSLR with my wireless remote and coming back in 10mins time. I reviewed the image on the screen and was pleasantly greeted with round stars :D
Everything was working so an hour after going outside I was ready to start my imaging run.
I wanted to primarily try M42 as my first attempt at this was in less than ideal conditions!
Scope: 250p DS
Camera: Nikon D200
Finder Guider: Atik Titan
6 x 600s subs, 4 x 600 Darks, Bias, no Flats

© Lee Diggle 2011

For the core I composited on two images. A 30s shot for the wider core and a 2sec shot for the trap.
Stacked in DSS and finished in Photoshop using a great tutorial:
In PS, various curves adjustments were done to tweak the colour balance and bring out the nebulosity. High Pass sharpening LAB sharpening were used to bring out some of the more subtle detail.
Before I got to this stage, I did try a 5min sub with no MPCC and it was quite apparent that there was coma at the edges. The MPCC has nicely sorted this out.
Second I wanted a quick bash at M45:
Scope: 250p DS
Camera: Nikon D200
Finder Guider: Atik Titan
3 x 300s subs, 3 x 300 Darks, Bias, no Flats

© Lee Diggle 2011

By this time the power was going in both my laptop and Powertank.
You can see some nebulosity coming out, but there is still some noise visible. A lot more subs needed for this one. Also it is apparant that the stars are not quite as round as in M42, not quite sure why this is, but for my first attempt I am very pleased.

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