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Message: <blockquote data-quote="Red_Shoulder" data-source="post: 3360177" data-attributes="member: 130635">Yes, just the element closest to the eye is 39-45mm focal length,  that's ok. The others are 50-55mm and 67mm (hard to measure these exactly) .So I plugged all 3 in to get 17.3mm-20.9mm or so for the whole thing, depending on how far apart the elements are. I still need to measure the objective's focal length,  but 7x at around 20mm would be 125-150mm range, like you'd expect. Based on another thread, these seem to be mid 80's or so, $80 new. Afaik,  aspherical lenses were not common in more-expensive camera lenses at this time, so I wouldn't expect them here. Also,  the diy ep I got off ebay (erfle) gives nice performance at about 60°,  and I don't think it was aspherical at $13. So hopefully, for the repair at least,  the element isn't aspherical.But if it is,  I might contact Mathews Optical and see if they'll sell me a few, or if they generally sell 1000+ at a time.</blockquote>