Which are the differences between manipulating colour with the HSL tool while developing a raw file than if doing some manipulation while editing a 16 bits file?

DxO PhotoLab
1

I have tried to find an answer to my question googling but couldn’t and I have asked in another forum but nobody quite answered what I was asking.

My question is: Which are the differences in terms of the quality of an image that one can get once in the editing process of an image, if having done some manipulations with the HSL tool while developing a raw file than if doing some corrections or manipulation ones processed, to a 16 bits tiff file (not to an 8 bits jpg, as there is a lot of information available about the differences among developing a raw file an editing a jpg file)?

For what I know (but correct me if I’m wrong), though corrections can’t be applied to the original raw data (as raw data can’t be altered nor edited), manipulation of values (reassignment of values?) done during the development of the raw file will be applied to the image / file that will result from the development process (or something like that).
But once you have developed the raw file, the result is a pixel image, being it a tiff or jpg or whichever file format you chose the exportation to be done to (an image), but though it being a 16 bits per channel or whichever value, an image nevertheless, not the data of the shot as perceived by the sensor and as registered by the camera in a raw format file.

Therefore, developing a raw file is obviously not the same as editing an image file. Which doesn’t mean that maybe, if one fiddles with colour (hue, saturation and/or luminosity) while editing a 16 bits per channel image tiff file (if needed), there might be not a lost or not that much of a lost of image quality (as could be noise being added, or banding, or whatever) or maybe (as I would suspect but am not quite certain about) it is better for the resulting quality of an image to always fiddle with colour (with the HSL tool) while processing the raw file.

When changing a colour while editing a 16 bits tiff file, is the colour being changed or re-assigned as when doing so while developing a raw file?

I have been able to find a lot of articles on the internet about the differences of processing a raw file against editing a jpg 8 bits image file, but not which are the differences between the former, and editing a 16 bits per channel image file (although some are obvious, as the fact that all the information, as could be the details in the shadows or in the bright areas, that is not taken advantage of or is not “rescued” when developing the raw file, can’t be used once it has been developed simply because it won’t be there, that much I know).

Maybe what I am asking is obvious, so forgive my ignorance if it is.

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No matter what the file type PL doesn’t touch the original file. Any changes you make are non-destructive and only written out when you export a copy of the edited image

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Thank you Joanna for your answer.

I still have a question. Maybe the answer is implied in your response, so I hope you don’t mind me asking again.

I understood that If I work on a file of whatever format, this file won’t be touched when working on it in PL, and whatever done will be written to the export, not to the file being developed or edited itself.

But, say that (as an example) I change the Hue of a certain colour and de-saturate another colour (if I apply just this two corrections). If I do this while developing a Raw file, will the result for the exported image be better than if I do the same while editing a 16 bits tiff file (the same image, but once already developed from raw and exported to tiff)? Or would I obtain the same results indistinctly (in regard to the quality of the resulting image)?

I know (or at least have read) that I won’t obtain the same results in terms of image quality if say I change the hue of a colour or de-saturate it (or if I change the white balance) of an image while developing raw, than if attempting the same with a jpg file. The explanation, normally being that the result will not be the same because the jpg file only has 8 bits per channel (and therefore, not much of a tone spectrum). Would I?
What happens in terms of how good (or worst) results can be obtained for the image to be exported when fiddling with colour while working with a 16 bits tiff file?

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Correct

There are certain corrections that benefit from being done on a RAW file (like white balance and de-noising for example).

As you say, a jpeg only has 8 bits, therefore will tend not to produce such smooth tonal gradations as a RAW, which usually has 12-14 bits.

Other than that, the results you get are pretty much down to your skills with the tools provided. I have had excellent results from pretty mediocre jpeg files and rubbish results from RAW.

1 Like
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Thanks Joanna for your reply.