Controlling Raw Conversion

I’ve been a Raw Therapee user for some time but, probably like most users, I use but a small part of it. The RAW tab, for example, I’ve mostly stayed away from and have not been very clear on what it is about; my assumption has been that it was for someone who wanted to modify how the RAW conversion is done.

The other day I took some photos of fireworks, however, and particularly with my first few attempts, the light of the fireworks was blown out; it was nice and bright but there was none of the color that I had witnessed with my eyes. In post-processing, I just assumed these images were hopeless - though I did not delete them.

Today it occurred to me that this might call for help from the RAW tab. I reasoned that in the RAW file, the color should still be there but was lost in the RAW conversion; by the time it the RAW sensor data was converted to a pixel map the color was all gone.

What I needed to do was to clip the intensity pixels - perhaps using a control cage - to reduce the intensity BEFORE the raw processing created the image. Unfortunately, I was not able to find anything in the RAW tab that would let me do such a thing. But maybe I’m just missing something.

Is there a feature like this somewhere? Should there be?

First of all, check the raw histogram. That’s the third from bottom button just to the left of the histogram. If all three channels are clipped, then you’ve overexposed irreparably and you’ll never get any color back.

If it’s not fully clipped (ideally, only one color channel is clipped), enable the “color propagation” highlight reconstruction in the Exposure tab. That should let you lower the exposure compensation and pull in highlight detail.

Sometimes if you start getting wonky colors, you can try lowering the White-point correction in the Raw tab slightly. Sometimes it helps, sometimes it doesn’t.

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Paul everything you need to get more color in the clipped fireworks is in the Exposure tab:
http://rawpedia.rawtherapee.com/Exposure

For more relevant help you’ll need to share your raw file.

Thank you very much for those suggestions. They helped quite a lot.