[Leica] DMR: Hands on

[henningw at archiphoto.com (Henning Wulff)]

At 6:33 PM +0000 11/12/04, Frank Dernie wrote:
>Well it seemed to me that the fact that the completely different 
>amount of vignetting by the CV and Leica 21mm lenses suggested that 
>the vignetting  was due to the lens geometry as much as the focal 
>length. If this is the case then the supplied correction software 
>will correct for the lens it is meant to, but not necessarily any 
>other of the same focal length but different exit pupil position, 
>for example. That means if I bought one I could correct for errors 
>due to a Voigtlander 21mm, which I don't own, but not a Leica 21mm 
>which I do own.
>I had intended to buy one but now I have cold feet! I guess it is 
>fine if all your lenses are the CV ones.
>The other concern i have with correction of this type is that I can 
>only see how it can take place at the expense of dynamic range.
>Frank

Exactly. If the corners are underexposed by 4 stops (that's being 
generous to the 21 C/V) then if you shot at 200ISO, and that is what 
the center of the image is dealing with, then the software 'pushes' 
the corners to an equivalent of 3200ISO, and leaves you with 
significantly reduced image quality.

With the Leica 21ASPH, you could probably get away with using just 
the 'anti-vignetting' slider in Photoshop Camera Raw, and get an 
acceptable shot. It can handle 2 stops. Still a decrease in quality, 
but manageable.

>On 12 Nov, 2004, at 09:07, Mark Rabiner wrote:
>
>>On 11/12/04 12:55 AM, "Frank Dernie" <Frank.Dernie@btinternet.com> typed:
>>
>>>I think you are right Mark,
>>>Engineering a digital removable back for a film camera will have been a
>>>VERY expensive and difficult thing to do mechanically. I take my hat
>>>off to Leica for doing it. I expect any subsequent digital SLR will be
>>>a complete camera, and much easier to do.
>>>My hopes for the digital M plummeted following the physical
>>>implications of Henning's experiences with the Epson. I hope I am not
>>>being too pessimistic.
>>>Frank
>>>
>>Frank we've heard a whole lot of positive stuff about that camera since.
>>Tom Abrahamson loved it and so did the friends he leant it too who were 
>>many
>>and exuberant.
>>Went over big at the Williamsburg meeting.
>>Mark Davison seemed very positive on it.
>>Not without criticisms.
>>
>>Don't know what DMR means.
>>
>>
>>Mark Rabiner
>>Photography
>>Portland Oregon
>>http://rabinergroup.com/
>>
>>
>>
>>
>>_______________________________________________
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>>
>
>_______________________________________________
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