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What IS M8 raw?


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I'm very confused. I shoot raw (with jpegs for client review and backup).

 

Everytime there is a different firmware version, Edmund has to rebuild the profiles I am using.

 

What the hell are they doing to the raw files? Why does a firmware change what is supposed to be a coredump of the sensor?

 

Rather than raw, these things should be called crudite. Now, where's the dip. Oh, forget that, where's the booze?

 

Man, I would give my right something-or-other for a second M8 body, but gimme the RAW image. Quit messing with it. Don't compress it.

 

Dictionary definition -- Raw: what you least expect.

 

 

GUY, would you add this to your current request list: Leave the damn raw file alone!

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Why does a firmware change what is supposed to be a coredump of the sensor?

 

I think the issue is that a RAW file _isn't_ a straight copy of the data from the sensor. I'm sure someone who knows more about this subject can add more detail.

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Not just compressed Bill. My understanding is that all RAW files, whoever the manufacturer, undergo some processing before the file is written. This is not my area of expertise, but I may have a bit of a Google to find out exactly what is happening.

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Leica changed the colour matrix values in the exif which is used by dng decoders, the version 1.06 - 1.09 had the same values but these changed since 1.091 and remain constant in 1.092 and 1.102.

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Leica changed the colour matrix values in the exif which is used by dng decoders, the version 1.06 - 1.09 had the same values but these changed since 1.091 and remain constant in 1.092 and 1.102.

 

Eoin, I believe your version of the sequence of the color matrix values, BUT, why do Edmund's profiles have to change in both the releases following 1.091?

 

Leica is doing something else with this file.

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If you have a look at the following exifs from 1.06, 1.09, 1.092 & 1.102 you'll see the differences in the matrix values and where the change happened. Apart from any internal processing the camera does before it writes the DNG. The DNG decoder reads these values and other values (exiftool could not decode) to render the DNG. C1 however is different in that it has it's own method and profile to decode the DNG but thats so out of date now that we have had 4 firmware versions.

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Raw sensor data does undergo a fair amount of manipulation before being written out. For instance, if you use a 6-bit coded lens with an IR filter, the cyan corners are removed out of the Raw file first. In the DMR, vignetting is corrected and white balance is fine tuned when using ROM lenses. A lot of the manufacturer's "secret sauce" is how the firmware renders the data coming off the sensor and what happens before the Raw file is recorded. Obviously, a fair amount of control still exists for us users when we bring the DNG into our chosen Raw conversion application.

 

David

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