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View Full Version here: : Lagoon Nebula (M8) at 3 F-Ratios


FOOTPRINT
02-06-2006, 10:01 AM
Hi All,
Well with this welcome period of good seeing and clear nights Ive taken M8 at three different F-Ratios 1. 10" SCT at F-10 (with an F-6.3 reducer would have been a better choice) 2. with the ED80 at F 7.5 3. With the ED80 + reducer to F-5, all 6 Min. Exp. at ISO800 with the Canon (modified) and using CWB (will do the same lot using AWB for a comparison, weather permitting, close-up and wide views each have their interesting points, I like the F-5 best but would be better with the other nebulosity to the east of M8 showing, still trying to get it without overexposing M8.

cheers........Jim

JohnG
02-06-2006, 10:44 AM
Hi

Is that a single exposure of 6 minutes or a combination with the ED-80 at prime focus, I am looking at the differences with my shot with the Tak and an umodded 350D and your modded shots. It makes an interesting comparison.

Cheers

JohnG

Lester
02-06-2006, 12:30 PM
Good comparison Jim,

Yes I agree f6.3 with the 10" SCT would be interesting also.

tornado33
02-06-2006, 05:39 PM
Good shots there. Even at F10 theres plenty of nebulosity.
Scott

ving
02-06-2006, 07:32 PM
they are all great shots. i couldnt pick a fave if i tried!

strongmanmike
02-06-2006, 08:35 PM
Great dedication there and an interesting outcome Jim

I like the 80ED at the native F7.5 :)

Nice images.

Mike

FOOTPRINT
03-06-2006, 09:24 AM
Hi All,
Many thanks for your comments, and "JohnG" they were 4 x 6 Min. Exp. at ISO800- DF removed (should have mentioned this) last night I took M8 again using AWB (all red) at F-6.3 on the 10" SCT, and will post this also for an added comparison.


cheers.......Jim

Striker
03-06-2006, 09:31 AM
Nice comparison Jim.

I like the ED80 F7.5 the best but thats mainly due to a nice image scale.

Their all nice.

JohnG
03-06-2006, 09:41 AM
Thanks Jim

Might try a slightly longer exposure as well, I was comparing the Tak at f/8 with the ED at f/7.5. I did 12 x 80 secs. Good shots though.

Cheers

JohnG