Strange exposure compensation in PL5 (5.15.1)

DxO PhotoLab
1

In winter, I had accidentally set the exposure compensation incorrectly when taking pictures with snow. Instead of +EV to -EV. The display of these shots in DxO PL was strange. Now I made an exposure series of the same subject from -3EV to +3EV in steps of 1EV.

Screenshot_1_FRV
Screenshot_1_FRV990×128 26.7 KB

Representation FRV.

In PL set the preset “5-No correction” and opened the directory with the photos. The representation is as expected.

Screenshot_2_PL5_ohne Korrektur
Screenshot_2_PL5_ohne Korrektur935×136 28.3 KB

Now apply the “1-DxO Standard” preset to all the photos. The exposure correction is turned off. The display is as expected.

Screenshot_3_PL5_Preset Standard
Screenshot_3_PL5_Preset Standard933×137 29.5 KB

Screenshot_4_PL5_Werkzeuge

Next, switch on exposure compensation for all photos with correction “Center-weighted Integral”. The exposure correction of the photos is exactly opposite to the original exposure. The exposure is corrected with
+3, +2, +1, 0, -1, -2, -3.

Screenshot_5_PL5_Belichtungskorrektur ein
Screenshot_5_PL5_Belichtungskorrektur ein936×138 31.3 KB

If now the exposure is manually set to 50% of the original values. (+1.5, +1, +0.5, 0, -0.5, -1, -1.5) the exposure correction of the photos is OK.

Screenshot_6_PL5_Belichtungskorrektur 50%
Screenshot_6_PL5_Belichtungskorrektur 50%933×136 29.9 KB

Is this a bug or do I have a mistake in thinking?

Translated with DeepL Translate: The world's most accurate translator (free version)

2

My first guess: Smart Lighting changes exposure unevenly for bright and dark parts of an image, similar to what a s-shaped tone curve would do.

Smart Lighting and Exposure always interact. Therefore I mostly use SL, when I use it at all, carefully and at low levels.

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3

Your assumption is correct. SL was set to light (25). If SL is turned off, the exposure will be even.

4

Thanks, @Siggi. Please note that SL can also interact with vignetting correction occasionally. I had a few images that reacted strongly when image corners were in dark areas. in such cases, microcontrast and clearview added more issues. Using smart tools in parallel with “dumb” tools needs some extra care and/or attention.

1 Like
5

Hi @platypus, thanks for the valuable advice for me. Learned something again. :grinning:

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