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Message: <blockquote data-quote="FrankD" data-source="post: 2317294" data-attributes="member: 18544">Renze,What I was referring to in that sentence you quoted was a way of classifying some of the alpha class binoculars. They have very good object performance and their edges are good (overall performance). What some of them lack though is field of view potential. Many folks think a 60-65 degree apparent field of view is good but, as you mentioned, in comparison to what? Other modern roofs? Yes, it is in that case but what about in comparison to other binocular designs that have been on the market for 50 or 60 years? If we could design large ocular/wide field eyepieces at that time then what is stopping us now? Prism size and the limitations of the roof design? That is what I was lead to believe from what I have read on the subject so far.To clarify what "overall performance" is....Overall performance is a combination of good subject performance but good edge performance as well. You can call that a large sweet spot or sharp edges. Whatever you prefer. It also includes other factors that I probably just cannot think of at the moment.Pomp,I am glad to see your contributions on the forum. I forgot to mention that in your other thread.To answer 2 and 3, yes, I am sure exit pupil plays a role but in the case of the 7x42 and 8x32 comparison I think you also need to consider the greater depth of field that the 7x provides in addition to the larger true field of view. In my somewhat comparative example earlier I simply chose the 7x42 FL because it was a current Alpha 7x to use versus the 7x35 Sears porro.</blockquote>

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