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Message: <blockquote data-quote="Binastro" data-source="post: 3180929" data-attributes="member: 111403">David, thanks for that.Assuming your estimate for the size of Venus as seen in your 20×50 spotting scope is correct at six arc minutes.Why does it look so large?Is it the scope, your eyes are both?Yes, if you looked at Venus with a 20×50 spotting scope during the day it might look 12 arc seconds across.Actually, Venus is rather easily seen when high up during the daytime without optical aid. The problem is finding it. Unless it's very near to the moon, or you actually know exactly where it is, it is impossible to find. But if you find it it is surprisingly easy.The smallest star images that I have seen is probably with the Canon image stabilised binoculars. But this is for faint stars or at least not bright stars. When it comes to really bright objects such as Venus, even though the optics are clearly very well designed, the brilliant Venus is expanded. But here the exit pupil of the 18×50, for instance, is less than 3 mm. Most of the image stabilised binoculars even from other firms generally seem to have small exit pupils. Although the 10x42 Canon and the Bushnell do have larger exit pupils.</blockquote>