Aperture size Vs Focul Length - astrophotography
hope iceman doesn't mind me posting his reply in here. but i thought i'd get the wider community's feedback on the topic.
"Normally people would start with an ED80 instead of an ED100, because the ED80 has a shorter focal length and a faster focal ratio."
i know when i bought my dob years back everyone said apature is everything. but with these refractors your saying that the 80 is better than the 100 because of the focal length. how does this work. wouldn't the larger size allow more light to be captured. ??????
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