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Message: <blockquote data-quote="Binastro" data-source="post: 3475641" data-attributes="member: 111403">Hi James.Post 37.A c.1955 Hensoldt 16x56 would have I think, machine grinding and initial polishing maybe, but hand finished to the highest standards by skilled technicians who are a very rare breed now.There would be a lot of man hours.A top professional tells me that top lenses have to be hand figured still.I understand that many binocular optics are not even ground now but formed into shape. As soon as you remove skilled labour, lots of it, prices tumble.Sony are proud of their new aspheric machine producing large optics to about 1/40 wave.I mainly use binoculars for astronomy, stars, which are very high contrast objects. Loss of contrast is not serious but loss of transmission is a problem, giving a 0.5mag loss in star brightness compared to modern best.I tested the 16x56 against 14 good resolving binoculars. 12x to 20x. 50mm to 70mm.Only the Zeiss 20x60 is much better, but has a seriously curved field. It is of near astro quality.A top maker nowadays can make a special demonstrator of a best model to near astro standards. Most stock will not be the same.Astro standard means at least 50 per inch magnification without the image breaking down and the best achieve 75 per inch at least.This is very tough for a short focus binocular.</blockquote>