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Okay. I've attached some quick & dirty (and pretty awful) photos here to show what I mean about there being no visible benefit to the larger aperture of the 200mm reflector over the 80mm refractor.
Each target was taken within about a minute of each other with the two different scopes (as in I changed back and forth between OTAs for each target). Same camera, same ISO & exposure settings for each target. Imported straight into the computer, cropped for comparison and exported without any editing whatsoever.
Surely I'm not alone in thinking that there should be a lot more difference than this, yeah? The flattener on the ED80 takes the ratio down to f/6.4, but that's still more than half a stop below the Newt. It should be two thirds as bright, but somehow they're within 5% of each other.
(Apologies for the quality of the shots, they're awful! I didn't align at all, just plonked down the mount in an approximation of south and crossed my fingers. Actually had to move the thing halfway through because a tree got in the way of Mars. Enough to get the idea though.)
Might post these in a new thread and see if anyone can explain why this should be.
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