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361 points Tomte | 1 comments | | HN request time: 0s | source
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yjftsjthsd-h ◴[] No.43607646[source]
This isn't really my area, so I'm probably wrong... I'd always assumed that RAW files were, well, raw data straight off the sensor (or as close as possible)? In which case, you could standardize the container format, but I wouldn't think it was possible to have a standard format for the actual image data. Would appreciate if anyone could correct me (a quick skim of wikipedia didn't clear it up)
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buildbot ◴[] No.43607699[source]
Typically they are not to my knowledge! Though I am also not an expert. Most camera makers apply a fixed sensor profile, and possibly a dark frame to remove noise before writing out the values to whatever file. Some of them may apply lens optimizations to correct distortion or vignetting as well.
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tobyhinloopen ◴[] No.43608231[source]
The corrections are just metadata, the RAW data is still there. This is true for both DNG and ARW (Sony). Dont know the other brands. The corrections can even look different based on what program you use to interpret them.
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buildbot ◴[] No.43608269[source]
I don’t think that’s true in general. As a sibling comments points out, this is not true for some DNGs - for example, the output of an iPhone is in DNG, but with many, many transforms already baked in. A DNG might even be debayered already.

GFX 100s II’s apply a transform to RAW data at iso 80, see: https://blog.kasson.com/gfx-100-ii/the-reason-for-the-gfz-10...

I don’t know much about ARW, but I do know that they offer a lossy compressed format - so it’s not just straight off the sensor integer values in that case either.

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1. tobyhinloopen ◴[] No.43608437[source]
Okay true, but that's not the format's fault (:

The GFX 100s II thing is very interesting. Totally not what I would expect from such a "high end" camera.