Expected behaviour for TIFs output by PL9?

DxO PhotoLab
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My workflow involves a pre-print stage of sharpening (and sometimes, upscaling) in Topaz Photo after all the denoising, cropping, and tonal adjustments in PL9. When the 16-bit TIFF comes back from Topaz, the thumbnails show a proposal to download the JPG module that matches my OMDS body and lens combo.

I don’t shoot JPG, and I never noticed this behaviour in previous versions of PL (I have been using it since before it was called PL!) though my workflow is the same as in recent years…

Surely the optical corrections that are needed will have been applied to my RAW images before the export to Topaz Photo. Why might they be needed again, and in any case, the files are TIFF, not JPG?

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To prevent PL applying corrections to an RGB image set the default preset for that type to no corrections, via Edit | Preferences

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Thanks! But that isn’t my point. I don’t have JPGs at all. Well, not in the PhotoLab library. I was just non-plussed to see that PL was offering to correct them for a second time. Not knowing whether corrections in PL are relative or absolute, I can’t tell whether a re-application of the correction could be harmful. I had thought that PL would use the same correction modules for TIFF files as for RAW …

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PhotoLab sees a new file, notices that there is no module and proposes the download.

Whether your exports from PL are optically corrected or not depends on what your customising and export settings are. Nevertheless, Topaz’s export is new to PL and because you don’t have the non-raw module (jpg module) yet, PL proposes to download the module.

Whether the non-raw-module corrections are applied (unnecessarily) or not depends on what metadata comes along with Topaz’s exported file.

Well, If you do want to know what happens in your case, you can download the module and see if corrections are applied again. Choose a photo taken with a lens that exhibits strong vignetting and distortion. It will help to see if there is any over-correction or not.

The module is just called the jpg module because most cameras do RAW (proprietary or DNG) or JPEG. Older cameras do TIFF too, so it is easiest to think of a raw and a non-raw module. Nevertheless, “raw” is not a well defines thing, we usually assume that raws contain data as captured by the sensor without (or minimal) processing. JPEG format is well defined, other formats are more or less well defined and leave room for variations. More about TIFF

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