Zoom and tiff export alters colors

DxO PhotoLab macOS topics
1

Hello,

I use Photolab 6 to process .rw2 files from my Panasonic S5.

On one photo, when I export it (tiff, but same for jpg, icc has no impact), colors are altered. Here are photolab screenshots, left is the processed raw, right is the exported tiff

diff
diff1555×433 134 KB

First I suspect an export (tiff or jpg) issue.

But later I realized when I zoom into the processed raw file, at 75% of zoom, colors suddenly change in the same way than the tiff file.

Does anyone has an idea of what is going wrong ?

Best regards,

Grégoire.

My configuration:

  • Photolab 6.19.0 build 76
  • Imac 21 Sequoia 15.1.1
2

That’s how it works… and users have been complaining about it for a long time.

3

Hello Wolfgang,

Sorry, I didn’t get your answer. You mean it’s a known issue (bug) ? Is it solved in latest PL releases ?

Regards,

Grégoire.

4

That’s how it works (has been for a long time) - zoom to at least 75% to get true colors.
And I’m sure it says this in the help too.
:man_shrugging:

5

Thank, its clear now. But why the same color alteration also exists in exported tif file, at full resolution ?

6

Here is an example.

the raw-file ← || → and exported as tif

Screen Shot 12-10-24 at 10.11 PM
Screen Shot 12-10-24 at 10.11 PM892×628 674 KB

Screen Shot 12-10-24 at 10.12 PM
Screen Shot 12-10-24 at 10.12 PM896×610 793 KB

But the tif file on the right does not show the color variation on the guitarist’s ring,
maybe CA, quite common with very high contrast.

( Please note that the bluish reflections are caused by the stage lighting. )

7

You can only see real color at 75 % zoom or above in main view (and under 24(?) %).
Inbetween those values you can’t see what you’ll get, colors are (can be ?) distorted.

That’s a “feature”; not a bug. ???

8

I mean : In the exported tiff file, opened with Photolab or native apple viewer shows the same distortion, without zooming.