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Message: <blockquote data-quote="Surveyor" data-source="post: 1534374" data-attributes="member: 50720">Henry, This is a very good idea, Henry. This prompted me to photo a Leupold 7x20 IF (labeled Leica Red Dot) that is the only binocular I have that will make me queasy when I am using them in a plane or helicopter.  Instead of the usual rolling ball this binocular appears more like pulling a tablecloth with a landscape scene on it across a round table, with maybe a very slight dome to it. The last 10% from the center looks like the table cloth is going straight down, the view expands very quickly from the trailing edge and compresses very quickly on the leading edge while getting less severe as the view travels around the outside of the view to the top and bottom and then increasing compression as it approaches the trailing edge. Looking at edge’s, in a normal still view, you see a little pincushion, then in the last 15 to 20%, the pincushion changes to barrel distortion, very weird. I have over 10,000 hours in aircraft and these things darn near make me airsick. They are very sharp in the center and I like them, I just have to avoid panning or movement with them. Look at the very ends of the grid lines. Looks to me like the field stop encases the lens so that the edge distortion is prevalent. I have attached the measured angles, though these are quick and rough, limited distance of about 200’. Also pictured, my "protractor". BestRon</blockquote>