Archived posting to the Leica Users Group, 2006/10/12

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Subject: [Leica] LHSA meeting in Wetzlar; Leica Camera AG
From: henningw at archiphoto.com (Henning Wulff)
Date: Thu Oct 12 12:46:07 2006
References: <001c01c6edc5$2d2a6090$6401a8c0@FrankDell2>

At 11:10 PM -0700 10/11/06, Frank Filippone wrote:
>If you need to predistort to allow oblique rays to present with 
>higher gain, then this is done in SW using a location algorithm in
>the camera before the data goes for storage.  Essentially, you 
>change the gain dependent on where the pixel is on the sensor array,
>therefore upping the gain for pixels that need it.
>
>I repeat, this would be done before the storage of pixels in the ADC 
>that converts the electrically stored energy from analog to
>digital values for the computer.  The RAW  ( and all other) data 
>would have already been corrected for gain. 
>
>We did this years ago for correcting certain optical sensors that 
>had to have flat gain across the array.  It is really pretty easy
>to do.
>
>Mind you, I have no inside information at all on the workings of the M8.
>
>Of course, I could be wrong and it is all marketing hype......
>
>Henning, did you get to try the M8 with coded and uncoded lenses of 
>the same type?  For inastance, the  24ASPH  from a few years ago
>uncoded, and the same lens, but coded?

No I didn't. I didn't have any coded lenses. I did use Leica lenses 
from 21 to 135 of all types, including the Ti-Elmar and old as well 
as new, and the 12, 15, and 21 CV lenses. The latter three show very 
severe vignetting on the RD-1, so I was particularly critical in 
examining the results from those. They didn't seem to show as much 
vignetting as they do on film, so that's why I wouldn't send my 
lenses in.

Other types of correction, as for example CA and colour fringing, 
were not issues either. There was a slight bit, especially with very 
old lenses, but that's to be expected. New lenses from the last 20 
years behaved very well.

I shot RAW and jpeg together for most shots.

-- 
    *            Henning J. Wulff
   /|\      Wulff Photography & Design
  /###\   mailto:henningw@archiphoto.com
  |[ ]|     http://www.archiphoto.com

Replies: Reply from red735i at earthlink.net (Frank Filippone) ([Leica] LHSA meeting in Wetzlar; Leica Camera AG)
In reply to: Message from red735i at earthlink.net (Frank Filippone) ([Leica] LHSA meeting in Wetzlar; Leica Camera AG)