Archived posting to the Leica Users Group, 2001/07/31

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Subject: RE: [Leica] Leica Quality versus Medium Format
From: "Austin Franklin" <darkroom@ix.netcom.com>
Date: Tue, 31 Jul 2001 20:14:22 -0400

>    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.

I am honestly curious, where did you get that info?  Were the both at the
same contrast level, and what was the contrast level used?

>    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.

Yes, but that depends on what the resolution of your metering system is...I
doubt, though the Mamiya shutter may be able to maintain the speed to 1/10
of set speed, that the meter will be near that accurate.

>    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.

At what contrast level are each tested at?

Replies: Reply from Mark Rabiner <mark@rabiner.cncoffice.com> (Re: [Leica] Leica Quality versus Medium Format)