It's an interesting question. In theory at least, the demosaicing should still work since it follows up/down trends and since ALL of the data was inverted, it would still work. The problem comes in when you want to apply the white balance, tone reproduction curves, and the ICC profile: unless those are mathematically inverted, you'd get the wrong color in the end if you invert before those steps.
Ultimately, you'd want to get what the camera actually saw to look just like the negative and then invert as the last step. Of course, that makes visual editing difficult: it might be possible to invert to a positive just prior to application of fill light, exposure, and other visual edits so that the editor could be used in a positive instead of negative fashion. It might also work to invert at an early stage (say after WB and demosaicing), apply fill light, exposure, etc., invert a second time (back to negative) before applying the ICC profile, and then invert a third time to get the positive back at the end. Fortunately no data loss is incurred due to inversion so you can invert as many times as you like without losing data. To know anything more, I'd need some sample raws of negatives.
Mike
Hello Mike,
The raws of color negatives are on their way to you by WeTransfer. I wrote a separate email to explain some aspects.
Met vriendelijke groet, Ernst
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