Hallo, I just put my FA 1.4/85 and my 24-90 on my camera and compared the field of view on 85 and 90 at infinity. The zoom has a longer focal lenght than the 85, maybe 88? I think that the FA* 85 has a focal lenght of about 85. I compared it also to the FA 2/24. There it looked the same. I think the zoom is longer as 80. Ones I have measured my SMC-F 28-80 and it was 77 at the long end. I do not know how you did your measurement, but I think the 24-90 is not far from the specs. regards R�diger
Von: keller.schaefer <[EMAIL PROTECTED]> >Some weeks ago I inquired here about the FA 24-90 lens quality. Subsequently I >bought the lens and shot some film with it. I would rate the optical quality as >very reasonable and the mechanical quality as not-so-good. > >What puzzled me was the fact that when looking through the viewfinder the lens >in the longest '90' mm position still had a shorter (!) focal lenth than my M >2,0/85. I tried to verify this by mounting the remnants of an old ME Super >K-mount to the lens standard of a view camera and attaching the lens to it. As >the difference in distance between lens and film (when moving the lens from >infinity to 1:1 magnification) equals the focal length, I was able to measure >this with some precision. > >The longest focal length turned out to be 81 mm (I'd say plus or minus 1 mm). > >I have also tested some other Pentax lenses: >M 2,0/35: 34,8 mm >M 1,4/50: 49,2 mm >M 2,0/85: 83,9 mm >M 2,8-4/40-80 at 80 mm: 78,9 mm >and found these are quite close to what the lens designation says. > >Pentax Germany did not dispute my measurements but admitted that the 90 mm >designation is an exaggeration for competitive reasons (...everybody does it >like that). > >So, effectively, this lens is an 24-80. > >I thought you might be interested. > >Sven >
