Mackinaw
Think Different
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- Mar 13, 2005
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My father, now retired, was an optical engineer. I found a copy of a 1971 Popular Photography magazine at my parent’s house at Christmas. There was an article in it describing Canon’s latest 50mm FD lens with an aspherical element. In the page margin was a large note written in bold letters: “REJECTION RATE!??” Before mould and polish processes were developed, hand profiling of aspherical elements was slow, difficult and error prone. Luckily, things progress.....
Canon was one of the first companies to use machines to grind and polish the aspherical surface of a lens. The first version of the FD 55/1.2 aspherical (1971) was hand polished and expensive, 147,000 yen. The 1975 machine-polished surface of the 55/1.2 aspherical cost 80,000 yen. The prices are from the Canon Museum website. I own a FD 55/1.2 aspherical (machine polished surface) and it is excellent.
Jim B.