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Old June 11th 07, 12:41 AM posted to alt.binaries.pictures.astro
Richard Crisp[_1_]
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Default ASTRO: Experiment in Astrophotography 128s_800b.jpg [1/2]

the first two came through nice

look good

the third did not appear


"George" wrote in message
...
I did some observing with friends last night, and tried out a new set up. I
used the mounting bracket on my 8" newtonian to mount a Canon 300D digital
slr camera and an 500mm 'finder' scope to my german equatorial drive. Using
this set up I shot some wide field images of the milky way from Cygnus to
Saggitarius. The three images below are the best of the bunch I shot last
night.

The lens on that camera is difficult to manually focus at such small focal
lengths (18mm), because it was designed for autofocus. These are
compressed files, so the detail is not as good as the full resolution
versions. Also, that lens appears to have some chromatic aberation (which
I guess is not surprising considering the aperature value used (f3.5). Or
it may have been a dew issue. I'm not sure. Also, when you zoom in on the
full resolution images, it becomes apparent that the images weren't very
accurately guided. I'll have to work on that issue. But they do show more
detail than I was expecting. Anyway, here they are. All of the images are
single exposures. They were taken at 18mm focal length (wide angle), at
ASA 800, at an aperture of f 3.5, and are approximately 2 minute
exposures. Yeah, dark, steady skies for a change. Taken on June 9-10, 2007
at Taylorsville Lake, Kentucky. The graininess is partly due to the ASA
level used at such a short exposure. I am currently working on stacking
the images in order to increase the number of photons in the images in
order to increase the resolution. If they come out better, I will post
those as well. Enjoy,

George