Quote:
Originally Posted by AstroJunk
I'd have to say that if the 25 didn't blow your 18 away in every respect then it had a poor mirror or the seeing was bad.
No disrespect to your 18 incher, but that's physics!
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I may be wrong here, but aren't the exit pupil and magnification at a given exit pupil in a linear relationship with the aperture? If that is the case, then the 25" would show the same object at the same apparent brightness just under 1.4 times bigger that the 18", assuming the apropriate eyepieces are used. From experience, I know that going from 100x to 140x doesn't exactly open up new dimensions. A factor of 1.4 in power increase may be "interesting", but leaves my socks firmly on my feet, sorry.
Heck, my eyepiece increments are more than that. I can see why Stephen was underwhelmed by this improvement, given that going from 8" to 12" gives a greater improvement than going from 18 to 25. Not to mention the dollars. Diminishing returns here big time, it would seem.
Correct me if Im wrong though.