Archived posting to the Leica Users Group, 2001/07/31
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]This is actually rather simple. Let's compare Mamiya 7's 80 mm F/4 vs Leica 50 mm f/2 summicron. At optimum apertures for both, the cron can resolve 110 lpmm, and 80f/4L can resolve 75 lpmm. Yes, Leica is better in raw resolving power. Now, take the size of the negative into cosideration. 24x36mm vs. 56x69.5mm, pick the lowest linear difference (the area difference is VERY misleading)and multiply: 110 x (36/69.5)= 57 lpmm for the cron when enlarged to the same size as the Mamiya 80mm f/4L. The winner? Mamiya. Don't forget also that in terms of exposure accuracy, Leica's ancient, mechanical shutter can be off 1/3 EV, while Mamiya's electronic shutter is about 1/10 EV. If both were metered correctly, Mamiya will expose more consistantly which is also critical for attaining that maximum resolving power. By the way, the 110 lpmm is an overestimate, I've seen literature saying the cron can do 90 lpmm. I think Erwin Puts said it can do beyond 100. - --- John S Payne <jpphoto@hci.net> wrote: > Hello all, > Sorry to be off topic but... I need some off list > advice on purchasing a > film scanner to do MF and 35mm color, b/w, and > transparency work. Thanks > in advance. > Regards, > John Payne > www.johnspayne.com > > __________________________________________________ Do You Yahoo!? Make international calls for as low as $.04/minute with Yahoo! Messenger http://phonecard.yahoo.com/