Negative lab pro convert problem


I am using negative lab pro trial v2.1.2 with lightroom classic. Once I hit convert my photo stays negative. Can anyone help me with this problem? Using mac os x 10.15.6

First, make sure you are hitting “CONVERT NEGATIVES” and not the “APPLY” button… some users will mistakenly hit the APPLY button before they have converted, in which case, Negative Lab Pro will basically just exit without doing anything.

If you hit “CONVERT NEGATIVES” and it appears to be working, but then when it returns to the plugin, nothing has changed, make sure you are using the latest version of Lightroom Classic.


Thanks for the reply. My lightroom cc is up to date, 9.4. And I am hitting convert instead of Apply.


I am hitting convert and using the latest version of lightroom cc.


I notice in the bottom right of your screenshot, there is a smaller window where it appears that it has been converted properly.

Also, curious if you see it appear converted if you start moving one of the sliders in Negative Lab Pro, or by switching to a new window, and then switching back. If either of these makes the image appear correctly converted, then it is likely an issue between Lightroom and your graphics processor. In which case, turning off graphics acceleration should fix it (go to “preferences”, then select the “performance” tab, and turn off any graphics acceleration).


Hey Nate,

I have a similar problem.
The NLP window implies, that the picture is converted… but it still appears as a negative.

I tested the same file on a second PC in a different catalogue, where hardware acc. is deactivated. However, it was not convertable.

In the last two months, I converted about 3000 negatives and this problem appeared on 2 pictures.
I use Lightroom v10.0 and the latest NLP version.
The most disturbing part is the batch process: For example, when I convert 100 pictures in a row, all the pictures are displayed as unconverted. Then I have to find the corrupted file by picking each file with NLP. When the selected files does not include the corrupted file, they will be displayed correctly as positive immediately after starting NLP. And then I can press “apply”.
Afterwards, I have to find the original negative and digitalize it again.

Actually, I wanted to send you the raw files, Nate.
But… Now, after some weeks, I tested the two pictures again, in a new catalogue.
The problem is gone… the pictures got converted.
However, I guess the problem has not been solved.

Anyway, do you need these two files?



It would be great to see the files that weren’t converting properly. If you can email a link to me at (or send me a PM on the forum), I will take a look and see if I can find anything unusual about the file.