Ken Norton wrote:
> Just a note on DCRAW conversions with Oly files. When dealing with saturated
> yellows and oranges, DCRAW will tend to create a checkerboard pattern in the
> highlights. This is particularily harsh with the E-1, but I believe other
> bodies (specifically the Kodak sensored ones) will do this too.
>
> Rumor has it, it's because the RGBG pattern is actually reversed in the
> Olympus. Instead of RGBG, its GRGB. Inotherwords, the mapping start point
> is off in DCRAW. Initially, ACR hadthis problem.
>
Have you checked recently? I saw in the code when I was messing about
with getting the A650 IS going that there is special handling for Oly
RAW files.
Also, there are four different demosaicing algorithms available.
More - Those applications that use dcraw or its code within their own
GUI and other bells and whistles don't necessarily use all of it.
RawTherapee, for example, uses dcraw to get the RAW data out of the
files, but applies its own demosaicing algorithms. There is a comparison
of a whole lot of different demosaicing results here.
<http://www.rawtherapee.com/RAW_Compare/>
They aren't for ORF, but I find it illuminating to see the wide
variation. The effect you have seen may have nothing to do with the RGBG
pattern and everything to do with choice of demosaicing algorithm.
Moose
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