I am shooting a lot of vintage negatives of film. I invert the negative-image in Develop with curves, to create a positive-image.
I would like to import these 'positive-images' as duplicates into my Library, so they can be affected by Develop sliders... without the developments having to be in-the-negative.
When you invert an image... the result is a positive.... but if you slide the EXPOSURE slider in Develop to brighten... you have to slide to the negative... to increase the exposure. This makes it tricky when you are working with hues.
I can export everything as TIFFs... and reimport, but I lose other RAW features and benefits.
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Re Negative Lab Pro, there's a long, detailed discussion about it in this thread, including comments from the developer:
"I lose other RAW features and benefits"
What do you see as the benefits?
I'm wondering about this too.
A 16-bit tiff derived from a raw file that contains all the information in the negative should be as good as a raw file.
My suggestion is to use Edit in Photoshop, invert the image using a Curves adjustment layer with the Color negative preset, which does a pretty good job. And while in Photoshop, I would retouch any dust and scratches, which is done much more easily than in Lightroom. If there is a lot of dust, Lightroom will slow down to a crawl.