Export to JPEG creates artifacts

I was searching for this topic, but could not find anything comparable. I have a lowkey image, which I wanted to process with DxO PL 5 (latest version). When I export it to JPEG or even TIFF PL create block artifacts in the dark areas. The vignette filter is disabled (I saw the bug description). When I process the same CR3 raw file with Mylio I do not get such artifacts. So PL is doing something wired here.
Artifacts (increased brightness to show the issue):

Export without adjustments:

Jpeg export from Mylio:

Increased gamma, no artifacts:

Original (increased brightness) as it is displayed in PL:

To this looks like a bug, as other editing software (Mylio) can export the image without issues.

Is there something I could change to get around this issue? I used for this picture Mylio instead of PL for editing, as it did not work as expected.


@Tobi , you could attach the original raw file and the sidecar .dop file for us to check. Please also add a screenshot of the output settings you used.

I see some posterization, which is usually caused by insufficient bit depth and adjustments that surpass “normal” adjustments by a wide margin, like e.g. brightening an image that was way underexposed:

Both images have been raised by 7 EV using the tone curve (change from 255/255 to 15/255) and the Exposure Correction tool set to +3. No other corrections were made.

Which OS are you using, Tobi ?
_ I think that bug is only relevant to Mac users … I’m not seeing any problem on Win.

John M

It seems like banding issues, which normally occur in dark areas when there are little bits available.

You said you also have it when exporting TIFF. Did you try 16bit TIFF, you’re sure?
Sometimes adding a small amount of (almost invisible) grain could help. But that would seem like a workaround that should not be needed, in my opinion.

If the 16bit exported has no issues, but JPEG / 8bit TIFF do have issues… it means that DxO seems to change it entire pipeline to 8bit or something when exporting to a 8bit file format. Which seems wrong (normally, you run the pipeline in the full quality available, and convert it to the output format as the last step when everything is done).

The vignette filter is disabled (I saw the bug description).

Did you also try to disable the ‘Distortion correction’ to see if that is causing the problem? See my topic on banding issues with the distortion correction: Block pattern / banding caused by distortion correction

Never got an answer :unamused:

we ‘need’ your pic → raw-file, screenshot of your settings … :slight_smile:

Hi guys,

thanks for your feedback. I need to check why I did not receive any notification. Sorry for the delay. I am using Windows 11 as OS. To make the effect visible, I do not need to change image, just apply PureRaw and export to JPG.
Here a screnshot from the live preview of the CR3 (on the left I
brightness and gamma to show artifacts):

Here is the export of the same picture to jpg (quality 90):

Here is the export of the same picture to jpg (quality 100):

Here are the used basic settings for the JPG export:

For tiff I have to correct my original post. Within DxO PL it is fine, the artifacts I saw where within Mylio and disappeared when adjusting the sliders. So tiff should be alright (I will edit the inital post - I can not edit :frowning: ):

Here the same picture without adjustments exported within Mylio to jpg, in the dark areas I see some to be expected artifacts. Something just goes wrong in DxO PL. I had a similar issue with another image in the past, but did not further investigate. When I find it, I will add it to the thread:

@LexB: It is not the distortion problem, the vignetting feature is not active in my export (I use this on a rar base anyhow).

Here is a cr3 file with the dop file which also created artifacts for reproducing the issue:
IMG_0277_DxO.zip (9,4 MB)

Hi Tobi,
what I see on your jpeg is banding. I exported your pic as jpg with 100% and had a bit less, but it was there.

Exporting the same thing as 16 bit tif – no banding.

Changed the exposure (+ 1,94) and exported as jpg with 100% – no banding.

Hi Wolfgang,

why is this only happening in PL and not in another tool like Mylio? The workaround here is then the export to tiff and then creating from the tiff the jpg in Mylio. For me this still lools like a bug. Another example: On the left you see the JPG export from DxO PL, on the right you see a TIFF exported to Mylio and then a JPG generated by Mylio out of it:

There is some kind of banding also on the right, but the overall result is better than from DxO PL, here with increased brightness:


Hi Tobi,
already too long ago – I lost ‘track’. :slight_smile:
And I have no idea about Mylio …

With JPEGs it’s always difficult due to compression artifacts and limited bit depth → see @Platypusanswer.

Also, JPEGs are better suited as ‘output files’, which means, don’t work on them anymore.