I just started using Negative Lab Pro in Lightroom 13 and so far its great, except for an odd quirk.
The controls for highlits, shadows, etc operate backwards. Plus is minus, shadows are highlights. I’m getting used to it but I’d love it to be normal.
It’s not that odd really, the image has been inverted. It’s covered in the Guide, you can save to a tiff, 16-bit if you like, when you have got the image close to how you want it and then the controls will be normal again.
The controls on the second tab of NLP work as expected. They can be used with already NLP-converted images. Just press the hotkey to launch NLP for the selected image(s).
Using Lightroom’s controls not only operate backwards, they can also change the colours of a converted image. It’s therefore advisable to use the controls of NLP’s second tab. Using positive copies works too, just be aware of the space required by a 16bit TIFF.