At 12:11 08.11.01 -0800, you wrote: > Focal lengths appear to be somewhat "non-linear", IMHO. That > is to say that just a few mm's difference at the short end > will make far more difference than a much larger difference > at longer focal lengths. Look around for a "field of view" > chart and check the differences.
I agree that the angle a lens covered should be taken as a basis, but that still does not explain the story: Lens angle x factor to (mm) (degrees) previous: 15 111 17 103 1.1 20 94 1.2 24 84 1.2 28 75 1.2 31 70 1.1 35 63 1.1 43 53 1.2 50 47 1.2 77 31.5 1.5 ?????? 85 28.5 1.1 90 27 1.1 ... ... ... There is still an unexplained jump between 50 and 77! Knut - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
