ASTRO: Moon, large file

Back in June one of my only clear nights was a bit past half moon. So I
decided to try for it though my planetary results are mediocre at best.
So I set up a series of 30 moon shots planning on stacking the best
ones. But the usual happened. I got one and the computer crashed.
Never did that before during a session. Took about 10 minutes to get
things up and running again and the camera cooled down again, by then
clouds rolled in and I had to call it a night. So I got one shot to
chose from for "stacking". With such a limited selection I decided to
use all one of them. To get the exposure down to where it didn't
overload the CCD I had to use the H-alpha filter. So this is a 1/1000
second shot of the moon in H-alpha light through the 14" XL200R taken
unbinned with the STL-11000XM. I cropped out much of the black areas.

Rick

--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

Rick, you got good detail on the terminator side. One thing that I will
never understand is why the opposite side (the border between the bright
limb of the moon and the dark sky) is always a bit unsharp on images that
are focused on the terminator. I get the same effect in my images, with
different scopes.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...
Back in June one of my only clear nights was a bit past half moon. So I
decided to try for it though my planetary results are mediocre at best.
So I set up a series of 30 moon shots planning on stacking the best
ones. But the usual happened. I got one and the computer crashed.
Never did that before during a session. Took about 10 minutes to get
things up and running again and the camera cooled down again, by then
clouds rolled in and I had to call it a night. So I got one shot to
chose from for "stacking". With such a limited selection I decided to
use all one of them. To get the exposure down to where it didn't
overload the CCD I had to use the H-alpha filter. So this is a 1/1000
second shot of the moon in H-alpha light through the 14" XL200R taken
unbinned with the STL-11000XM. I cropped out much of the black areas.

Rick

--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".

The curvature of field in a SCT makes this tough to do. The R model is
better but not great. With several tries on focus I can find a good
middle ground but I only one one try and didn't quite hit it then the
computer and clouds said "enough!" and shut me down.

With Powermate projection my 10" F/5 Cave does a much better job of
flattening the field. See:
http://www.prairieastronomyclub.org/...johnson-01.jpg

Rick


Stefan Lilge wrote:

Rick, you got good detail on the terminator side. One thing that I will
never understand is why the opposite side (the border between the bright
limb of the moon and the dark sky) is always a bit unsharp on images
that are focused on the terminator. I get the same effect in my images,
with different scopes.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
...

Back in June one of my only clear nights was a bit past half moon. So I
decided to try for it though my planetary results are mediocre at best.
So I set up a series of 30 moon shots planning on stacking the best
ones. But the usual happened. I got one and the computer crashed.
Never did that before during a session. Took about 10 minutes to get
things up and running again and the camera cooled down again, by then
clouds rolled in and I had to call it a night. So I got one shot to
chose from for "stacking". With such a limited selection I decided to
use all one of them. To get the exposure down to where it didn't
overload the CCD I had to use the H-alpha filter. So this is a 1/1000
second shot of the moon in H-alpha light through the 14" XL200R taken
unbinned with the STL-11000XM. I cropped out much of the black areas.

Rick

--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".