> >I believe in Canon-terminology 3.5 is half a stop slower than 2.8. >Just like 4 - 4.5 - 5.6. > >If it really matters. > May be, but I'm not sure about that. I suspect it's the other way round. Canon chose to use 3.5 and 4.5 as "half stops" on bodies which can display half stops only because they have a bunch of lenses which have these as fastest aperture. If these lenses were really just a half stop slower than 2.8 or 4, I can't see a reason why they shouldn't have marked them with the correct aperture and also should have used those same values in their cameras. ------------- Don't know. Why would Canon have made ALL lenses f3.5 and f4.5? Maybe some clever marketing quy decided it looks better to have always x.5 when we are talking about half-stops. You know: 2.5 (e.g. FD 135/2.5), 3.5, 4.5. Also I wonder if Canon really would force people to use odd aperture scales in bodies which select aperture only in half stops. Example: You are using a 50/1.4 lens and by selecting 2.8 - 3.5 - 4 - 4.5 - 5.6 the camera would jump -- 2/3 - 1/3 - 1/3 - 2/3 - steps. That wouldn't look good (but on the other hand because of the small size of the error that wouldn't really matter either in which case you might be right after all). If I have time I may do some checks with an EOS-3. Vesa _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
