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rogerg
30-08-2006, 12:25 AM
A quick shot of NGC 6943 before the moon set (quite a brightly lit sky). Medium length exposure at 10x600s.

Not bad, main problem is distortion in the field mainly in the bottom left. I think I'll be checking that out next time I'm able, see if I can fix it but still retain F/5.75 (F/7.5 it's not a problem). Not quite sure what's causing it, suggestions appreciated.

Roger.

h0ughy
30-08-2006, 07:10 AM
nice one Roger, but how did you get the F5.75 in the 12"?

rogerg
30-08-2006, 10:43 AM
That's just what it happens to be with the combination of F/3.3 reducer and the spacers I'm using. It's actually the only way I can reach focus with the F/3.3 because of the JMI NGF-C between rear cell and reducer. I think that's the cause of the distortions too - if I had more room to play with varying spacers I'd probably be able to fix it.

Roger.