Astro Imaging Trial 2

August 29 2010
Clear skies again so its time to try astro imaging to improve my technique. Scope out and cooled by around 9:30. Polar aligment done but Im still having trouble with a single star alignment. The first attempt, although being successful, was not correctly aligned. I was trying to use Dubhe and Deneb but to no avail. When I select a target its nowhere to be seen. So I decide to try alignment again. This time I select Acturus as the alignment star. Alignment successful and to test it out I tell the scope to point to M31….spot on, just to the right of centre but within the 32mm eyepiece FOV. Success!!!!
So the plan tonight is to image M31, M13 and M82.
M31 is first on the list. My D200 is connected to my SW250P DS with the disassembled 1.25” EP adapter. I slew the scope to Shedir to sort out my focus with a couple of 10s exposures. I get the focus as neat as I can given the limitations with no live view and no direct computer download. Once sorted I then slew back to M31 and proceed to take my subs. With my camera set to ISO800 and a ¾ full moon I try 60sec exposures. In reality the exposures are recorded as slightly longer as I cover the scope at the start on and end to avoid the wobble associated with mirror slap. Tonight Ill just try 15 x 60s exposures with darks to follow.

© Lee Diggle 2010

Following M31 I slew to M13 to try my hand at something different. As with M31 I limited myself to 60s exposures and took 10 x 60s subs with darks to follow.

© Lee Diggle 2010
After this I finally decide to try M82 or the Cigar Galaxy (Bodes Nedulae). Same as above with 10 x 60s subs and darks to follow.

© Lee Diggle 2010

All images were stacked in DSS and processed in Photoshop CS4 after to sharpen, tweak contrast and remove gradients.
The shot of M82 is my favourite as I slewed the scope and took a 10s exposure without looking through and got a nice surprise when I could see the galaxy in frame.

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