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We asked camera companies why their RAW formats are all different and confusing

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361 points Tomte | 2 comments | 04 Apr 25 11:41 UTC | HN request time: 0.44s | source
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yjftsjthsd-h ◴[07 Apr 25 04:20 UTC] 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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1. tobyhinloopen ◴[07 Apr 25 05:53 UTC] No.43608218[source]▶
It's all float value arrays with metadata in the end. Most camera sensors are pretty similar and follow common patterns.

DNGs have added benefits, like including compression (optional) (either lossy or lossless) and error correction bytes to prevent corruption (optional). Even if there's some concerns like unique features or performance, I'd still rather use DNGs without these features and with reduced performance.

I always archive my RAWs as lossy compressed DNGs with error correction and without thumbnails to save space and some added "safety".

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2. schobi ◴[07 Apr 25 06:13 UTC] No.43608353[source]▶
Nitpicking correction: The sensors give you a fixed number of bytes per pixel, like 10 or 12 bits per pixel. This are unsigned integers, not floats.

Typically you want to pack them to avoid storing 30% of zeros. So often the bytes need unscrambling.

Any sometimes there is a dark offset: In a really dark area of an image, random noise around zero can also go negative a little. You don't want to clip that off, and you don't want to use signed integers. So there typically is a small offset.