Rawtherapee tone curve1 tone curve2


(Colin Pittendrigh) #1

I looked in Rawpedia. Perhaps I missed it but I did not find an explanation of the two tone curve menus in Rawtherapee. I can set either or both as linear, custom, parametric or control cage. A second dropdown menu has options film-like, standard, weighted standard, saturation and value blending, luminance and perceptual.

Blind trial and error seems to show some option combinations don’t do much while others make major appearance adjustments.

Both tone curves effect the appearance of the currently edited image. Do the two tone curves form a composite average somehow?

Rawpedia still needs a work. I’d be happy to help out but…I’m too much a beginner yet. I do love the software.

(Ingo Weyrich) #2

Curve 2 is applied on the result of curve 1

(Colin Pittendrigh) #3

Ah. OK. It makes a big difference to know what is really going on, rather than stabbing at a black box.

(Morgan Hardwood) #4

@pittendrigh Coling considering that there is already an A4 page full of text just about the curves, what exactly is black-box about them?

(Colin Pittendrigh) #5

…what is black box? Perhaps I missed it. I saw no discussion at all about two curves (1 and 2) and how they effected each other.

That tone curve2 makes changes AFTER and on top of changes from tone curve1 wasn’t easy to find, if it’s there at all.

Searching for “tone curves” returned a “create this page” suggestion. Perhaps a lucene or plucene search mechanism would better connect keywords to pages that are already there.

No one (not many anyway) read online instructions from beginning to end, as if they were a textbook. Internet online help and tutorial is all about keywords. That’s the brave new world we live in.

(Morgan Hardwood) #6

You didn’t miss it, you brought it up.

The tone curves are part of the Exposure tool, have you checked the Exposure article?

(Colin Pittendrigh) #7

…black box is a term I heard a lot when designing user interfaces. I’m retired now but it was a common term, way back when dinosaurs and Borland C++ first roamed the mid-to-late 1990s PC world. Black box is roughly synonymous with trial and error.

(Cranberry Carborundum) #8

I have checked http://rawpedia.rawtherapee.com/Exposure and it seems that nowhere does it mention explicitly how tone curve 1 and 2 interact. It is something we all take for granted

Subsequently, I think providing an option for changing the blend mode between the tone curves may be a worthwhile suggestion.

(Ingo Weyrich) #9

That was the reason for my reply