Archived posting to the Leica Users Group, 2002/08/11

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Subject: [Leica] B&W Kodak (OT - was: So you want a new Leica M series Body?)
From: Ian Watts <i.watts@virgin.net>
Date: Mon, 12 Aug 2002 07:17:32 +0100

David Rodgers <davrod@worldnet.att.net> wrote:
> 
> Thanks for posting the Kodak mono camera link. Like you, I find it
> interesting.
> 
> I always thought having RGB sensors was a waste for shooting b/w. Three
> sensors when one would do, and all. But I've obtained some interesting
> results tweaking separate RGB channels for a final greyscale. It's like
> adding filtration after the fact. I wonder how a camera designed for
> monochrome will work. Will it require filters or can filtration be dialed
> in? I use filters a lot in b/w.


This camera is interesting because, to the best of my knowledge, it is the
only digital camera generally available that will do greyscale/B&W properly.
Non-digital types may not be aware how much real data is lost in the process
of capturing with a conventional digital SLR and converting the results to
greyscale/B&W. Indeed, contrary to David Rodgers' statement above, digital
still cameras do *not* have more than one sensor and capture in RGB using a
special filter array to 'spread' the R G & B information across a single
sensor. Using the Bayer pattern algorithm, the information is interpolated
to create 3 separate channels. This results in a loss of real resolution.
Although the quality of this process can be very good, it is not perfect and
areas of small detail (e.g. twigs and branches on a tree) can end up
suffering from severe colour bleed and fringing (often resulting in ugly
halos). When you convert the resulting file to greyscale/B&W you are simply
converting the interpolated data - along with all the fringing, bleed, etc.

The beauty of the Kodak 760M is that, by only outputting to B&W it does away
with the Bayer interpolation process and, thus, allows you to capture with
the full resolution of the 6MP chip. Without the need to interpolate the
data into 3 channels (via the Bayer method), you will get a far superior
result free from the problems noted above.

Ian Watts




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