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Old January 24th 07, 06:20 PM posted to alt.binaries.pictures.astro
TheCroW
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Posts: 167
Default ASTRO: 2nd moon session (1)

Telescope: Bynolyt BynoStar SPN 130-900 / 25 mm occulair
Camera: FujiFilm S5500, photo in RAW and postworked.

My second time attempt of moon photographs. Still an issue with sharpness
(I don not have yet a mirror camera), but the seeing was bad so I am
rather pleased with the results.


These are darned good in my opinion for an early moon. It's never very
high, seeing is never good down low and then there's atmospheric
refraction to deal with. Usually a low moon is best seen through a
relatively narrow band (for inexpensive filters) red filter. I used
Lumicon's H-alpha filter due to its narrow band width but another club
member had good results with a Wratten 25 red filter. Red light, being
longer in wave length isn't bothered by seeing quite as much (about half
as much compared to deep violet light) and the limited color bandwidth
reduces atmospheric refraction. Since the moon has little color going
black and white doesn't lose much and gains a lot in image quality. For
color today you can use a computer to split out the three colors then
recombine them aligned. When I was trying this several years ago I used
Registax to align the three colors to get rid of the problem. But I found
the blue image was always fuzzier than the red and green was between the
two in sharpness. A good planetary shot takes as much, if not more effort
than a good deep sky shot. They are two completely different beasts to
deal with! For a shot processed this way of the moon only slightly older
than yours see:
http://www.prairieastronomyclub.org/...johnson-01.jpg

I think your scope is a reflector. I'm not at all familiar with the
brand. If a typical achromatic refractor use a yellow filter. Achromats
are usually better corrected in the middle of the spectrum.

With film I'd go thru 20 feet of 35mm film just to get one really good
shot. Now if I lived atop a nice laminar air flow mountain look at all
the film I'd have saved.

Rick


Yes, it's a Newton scope. And it was indeed low and atmosphere was restless.
And thanx for the redfilter tip!! Sure gonna follow it up!!!

Menno