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Double Stars

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#1 Mike W

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Posted 11 October 2013 - 08:41 PM

I've dragged my spotmatic and K1000 back out and want to shoot some double stars. Have a 102 f11 and a 102 f8.6
I'm thinking I might have to use eyepiece projection. I prefer black and white but suppose that wouldn't help out a colorfull double! Any film suggestions?

#2 Nebhunter

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Posted 11 October 2013 - 09:17 PM

Eyepiece projection should do the trick and get the magnification required for this project. B&W film - I might suggest Ilford HP5+ as has good reciprocity, and red response if that helps? Fuji Acros comes to mind as well - nice fine grain. But there are some double stars with nice colours - Alberio and others whose names escape me at this time. Robin egg blue and orange/red combinations out there would make for a nice frame. Kodak Gold for colour in 35mm would be my choice.

#3 Mike W

Mike W

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Posted 11 October 2013 - 09:53 PM

I was thinking Kodak gold 100 or 200. I used Gold 400 for this comet shot on but that was 50mm f/2 @ 3 minutes. I think I'll bracket some shots of some different mag. stars and make up a table for reference. Should be fun!

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#4 Mike W

Mike W

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Posted 12 October 2013 - 06:54 AM

quote]I've dragged my spotmatic and K1000 back out and want to shoot some double stars. Have a 102 f11 and a 102 f8.6
I'm thinking I might have to use eyepiece projection. I prefer black and white but suppose that wouldn't help out a colorfull double! Any film suggestions? [/quote]

Ok, if you divide the telescope f/L by the eyepiece f/L you get the magn. for that eyepiece. How to you find the magn. for just the scope? :question:
880 f/L and 1100 f/L

Talking to Alan French it seems that dividing the focal length by 50 gives you the prime focus magnification. As I thought Double star photography will definitely need eyepiece projection. My 880mm will only give 17X at prime focus! Not gonna split to many doubles at that power.

Don't know why I quoted myself!






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