[quote name='genotypewriter' timestamp='1299897785' post='6683']
Dcraw won't evolve by itself if you stick to a single version like I said and not install the new versions.
You also will only need to upgrade the dng converter when you're upgrading the camera used for the test, which is very infrequently. Either way, the quality of the raw files will be determined by the raw converter, draw, the dng converter won't change the quality.
[/quote]
As I said, this doesn't change anything. DNG is not the simple and fixed format many believe it is. Especially when using the compatibility option for "ACR 2.4 or later", RAW files of some cameras are converted to linear DNG (even if you unchecked this option, since some sensor RAW formats simply cannot be reproduced in DNG RAW). Linear DNG means the RAW file is run through the demosaic algorithm of the DNG converter ... which uses the same routines as ACR with the same version number. So, with newer DNG converters, you're bound to use the evolved demosaic algorithms. With different quality in different versions.
The only other option would be to embed the original RAW data into the DNG, but then of course one would need a RAW converter that knows and understands this data. Which, for a rather new camera, means you'd have to use a current converter. And of course it would be way more simple to use the initial RAW file in the first place, instead of embedding it in another format.
In addition, DNG itself is a constantly evolving format.
So, problem not solved.
-- Markus
Dcraw won't evolve by itself if you stick to a single version like I said and not install the new versions.
You also will only need to upgrade the dng converter when you're upgrading the camera used for the test, which is very infrequently. Either way, the quality of the raw files will be determined by the raw converter, draw, the dng converter won't change the quality.
[/quote]
As I said, this doesn't change anything. DNG is not the simple and fixed format many believe it is. Especially when using the compatibility option for "ACR 2.4 or later", RAW files of some cameras are converted to linear DNG (even if you unchecked this option, since some sensor RAW formats simply cannot be reproduced in DNG RAW). Linear DNG means the RAW file is run through the demosaic algorithm of the DNG converter ... which uses the same routines as ACR with the same version number. So, with newer DNG converters, you're bound to use the evolved demosaic algorithms. With different quality in different versions.
The only other option would be to embed the original RAW data into the DNG, but then of course one would need a RAW converter that knows and understands this data. Which, for a rather new camera, means you'd have to use a current converter. And of course it would be way more simple to use the initial RAW file in the first place, instead of embedding it in another format.
In addition, DNG itself is a constantly evolving format.
So, problem not solved.
-- Markus
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