Quote:
Originally Posted by toyos
Even the cheap 127mm Chinese Apo blew both reflectors away by far when used with the 4.5" aperture stops. The reflectors showed much darker backgrounds & tighter stars with the aperture stops, but the images were greatly dimmed too; while the refractors showed brighter & crisper images with dark backgrounds, fitting the definition of contrast better.
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The images in the refelectors were probably dimmer because you didn't bother to fit suitable eyepieces to make each combination give the *same exit pupil / magnification* in your comparison evaluation. In a quality reflector with enhanced secondary it is unlikely that there would be any significant differnce in light transmission, not anyway that would lead to the images looking `significantly dimmed'.
I used to demonstrate years ago a 70mm stop on my 8" F8 Newt against against my Vixen 70mm Flourite refractor. With both instruments running at 65X ( the 8" scopes lowest mag) the views were essentially the same. It was so demonstrative to remove the stop and show how much more can be seen with decent aperture.