PureRAW problems

I have experienced a problem with DxO PureRAW 2.
Sometimes, When I decrease the exposure of a shot in Lightroom Classic, the image takes on a purple/pink tint.
You can read about it at these Dpreview links:

DxO, I have been told this is a bug, please could you fix it.

Your problem with the two images you posted in DPReview is that they are both over-exposed.

I just downloaded them and opened them in FastRawViewer, turning on the over-exposure indicators…

The golden rule of shooting digital is to never over-expose, as it can be nigh on impossible to recover detail in blown highlights.

However, some software can be better at recovering highlight detail than others.

Here are two exports from PhotoLab 5 after having adjusted them, but with no global exposure adjustment…

So, despite the over-exposure revealed by FastRawViewer, PhotoLab 5 was well able to recover some highlight detail in both images. But, before you say it is the fault of PureRAW’s DNG file, here is an export of the DNG file you posted, with exactly the same adjustments, in PhotoLab 5…

Which leads me to think that it is LrC that is doing something wrong.


Here is a screenshot from Luminar 3, of the DNG file, with just the highlights level reduced…

I noticed the following:

  • C1 can read DxO’s linear DNG of that image without a color problem.
  • Topaz DeNoise AI can generate a linear DNG that does not create color problems in LrC
  • The problem may be camera-specific, as I could not reproduce it (lots of blown highlights) with another camera.

Indeed. Here’s a screenshot…

Please confirm that you are using the “Denoise and Optical Corrections Only” option when you’re exporting the linear DNG from PhotoLab and that’s the rendering that C1 is successfully reconstructing the clipped green channel highlights. Bear in mind that when the “All Corrections Applied” DNG export option is used in Photolab, there’s no color cast issue in subsequent edits done in the Adobe tools, but of course this comes at the price of accepting the color and recovery corrections applied in Photolab.

Also regarding Topaz DeNoise AI, my testing of it shows that it’s a mixed bag. Yes, it doesn’t have the highlight color problems seen here, but it’s accomplishing that by clipping the red and blue highlight channels to match the clipped green channel sky highlights. As a result, the sky is either completely or mostly blown depending on which options were used in Topaz.

The problem may not only be camera specific but also ISO specific. The two examples posted by the OP were taken at ISO 640, which is one of the intermediate “fake” ISOs “pulled” from the next full ISO increment in this Canon camera. I’ve asked in the DPR threads, but the OP hasn’t addressed my questions about whether he’s seeing the issue at any of the full ISOs.

I am yet to do my testing. I’ll do it today.
I did reply to you at dpreview.