Archived posting to the Leica Users Group, 2008/11/02

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Subject: [Leica] R10 news
From: frank.dernie at btinternet.com (FRANK DERNIE)
Date: Sun Nov 2 14:43:48 2008

In fact it is both. Leica have ameliorated the microlens problem by having 
the outer ones displaced inwards rather than directly over the light 
sensitive site. This is better than nothing but is of course approximate 
since the ideal position for each microlens is different for each lens 
design.
The more pressing issue is the IR filter. It only filters the design 
frequency with normal light rays, since it is an interference filter. As the 
angle of incidence changes the filtered frequency changes. For a SLR lens 
the exit pupil is sufficiently far from the image plane for the deviation 
from normal to be negligible. With most rangefinder lenses this is not the 
case and the correction needed for the effect is more easily applied if the 
filter is on the other side of the lens.
Neither of these problems can be completely addressed using current sensor 
technology.


--- On Sun, 2/11/08, Frank Filippone <red735i@earthlink.net> wrote:

> From: Frank Filippone <red735i@earthlink.net>
> Subject: RE: [Leica] R10 news
> To: "'Leica Users Group'" <lug@leica-users.org>
> Date: Sunday, 2 November, 2008, 5:43 PM
> Frank.. there are 2 issues.... one concerns the angle of the
> light rays as they attack the sensor.....not an issue of the
> IR filter as such. More to do with "bending the
> delight" rays to attack more at 90 degrees...
> microlenses.....
> 
> The other has to do with image "quality:"  This
> is the issue I have wanted to read about....
> 
> As far as other manufacturers offering removable filters,
> and the DIY mentality of removing... Doesn?t that have to
> do with trying to capture IR images?
> 
> Frank Filippone
> red735i@earthlink.net
> 
> 
> 
> The only Hasselblad which would qualify would be if they
> made a back for the SWC. All the others you mention have the
> lens exit pupil plenty far enough away fron the image plane.
> 
> 
> 
> 
> 
> _______________________________________________
> Leica Users Group.
> See http://leica-users.org/mailman/listinfo/lug for more
> information


In reply to: Message from red735i at earthlink.net (Frank Filippone) ([Leica] R10 news)