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Old August 6th 07, 05:52 AM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Default getting my feet wet - first pics - 4 attachments (1/3)



Ryld wrote:

taken afocally with an orion ST80 and a finepix s5200 camera....


The saturn shot looks a lot like my first Saturn shot though a 60mm
refractor. It was hand held on Tri-X film about 1953 or so. Equipment
was pretty crude back then! I don't know how low Saturn was when you
took that. When low you will get atmospheric dispersion which is just a
prism effect caused by the atmosphere bending blue and red light
differently. Also that scope has some rather strong color fringing,
least those I've looked though do at higher powers. Often with such a
refractor a yellow or green filter and taking it in black and white mode
will result in a lot clearer shot as you are limited to one color. You
can even do tri color imaging that way for color but will have to align
each image separately when reconstructing the color image. This is also
a good idea when atmospheric dispersion is involved.

On M44 you've found a drive is needed for stars. I made a barn door
drive out of an alarm clock gears (wind up) that I used with a $35 400mm
lens (about the same as your scope but less aperture) and got some
excellent deep sky shots. Most were lost when a limb came through my
roof 16 years ago but one of M31 survived taken with that no cost drive.
Do a web search for "Barn door drive". Mine was a double hinge one.
I'll post the shot separately.

Rick
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