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Message: <blockquote data-quote="typo" data-source="post: 3181243" data-attributes="member: 83808">Binastro,I had a couple of minutes to play with the 20x50 before I went out last night and I my recollection of the apparent size was probably out by a factor of two. 1/50 to 1/60 was closer to the mark but that's still pretty bloated. 14" should be ~1/600th of the FOV.  I only had time to have a quick look at what some ND filter placed between the eye and the eyepiece did to the apparent size. The stuff I used is equal to two photographic stops, a four fold reduction or 25% transmission. One piece didn't do a lot so I tried 3 which should give 6.25% transmission. I wrote down 1/200th of the field diameter, but to be honest I wouldn't trust my estimating skill with an angle that small. 1/200 compared to 1/600 is probably within my margin of error. It doesn't look like there is much prospect of doing a more careful examination today, but I'll have a go when I can.The way I understand it the bloating is almost entirely in the eye though optical aberrations and the point and line spread functions will have a minor role. I did discover some fine scratches on the eyepiece which probably explains why Venus appeared more spiky with the scope than the binoculars.David</blockquote>