RawTherapee Website release post (aka: we're not dead yet)

Hi @patdavid , as de facto maintainer (and having access to the Gitlab repo) I’m back after some time off. As I said before, it’s great that you’ve worked to help out the RT community in this way! Thanks a bunch.

Reading the introduction of the post, I have a few remarks (such as, who is Pat David? :wink: – I would not want people to think that they should now bother you if they have questions about RT… ). I have some edits in mind. Would you be okay if I made these modifications directly to the post?

1 Like

I reviewed the latest version and it looks good. A few minor comments though. For the camera-based perspective correction section, the main developers and main contributors are on the same line. There’s no bold formatting for the ones in wavelet improvements.
Speaking of wavelets, it’s still marked as to-do. I compared the wavelets tool between 5.8 and the dev version and played around with the new additions. Jacques’s post above is a good summary. If you need any clarifications, I’ll be happy to help.

My sense is some of the discussion went into documentation territory. I certainly pitched in my opinions with that in mind. A follow-up post would be nice. May COVID-19 scidattle and stop preventing our Pat from waxing poetic. :stuck_out_tongue:

Hi Roel (@Thanatomanic)!

Glad to see you! Yes, of course you can make edits directly in the post. If there’s something you want to offload to me please don’t hesitate to tell me also. I’m here to help.

WHAT?! I AM PAT DAVID. I thought everyone knew this already!! :rofl:

1 Like

Wavelet section added.

@patdavid and others

Thank you Pat for this excellent work, everything is perfect.

Thanks for including the module “HDR to SDR: A First Approach (Log Encoding - CAM16 - JzCzHz - Sigmoid)” which contains in its introduction (made together with Wayne @Wayne_Sutton ), the summary of this module.

This module (HDR to SDR) is a simple alternative to what has been done in Darktable (filmic, Colorimetry and in progress sigmoid, etc.). But as you will notice I continue to use in the code (which uses 32-bit data - float), the Lab conversions, which after many attempts pass at least 15Ev (with the images I have). Moreover, if you check the necessary boxes in “Settings”, a Munsell correction is applied to Lab which allows a perfect respect of the colorimetry, avoiding color drifts (especially in the red-orange and blue-purple).

The Lab mode has a big restriction, but when it is used in the output profile (to the screen), in this case because of the 8-bit coding, Lab is limited to 7Ev and brings a limitation to 120cd/m2. Let’s hope that profiles with their management system (here LCMS) will solve this problem. Note however that HDR monitors are not within the reach of everyone: a model capable of passing 300 to 400cd/m2 costs about 3000€, and one capable of passing 4000cd/m2 is around 30000€.

There are several links in Rawtherapee where I talk about the Lab mode and its limitations, they give additional explanations. Par exemple https://rawpedia.rawtherapee.com/Toolchain_Pipeline#Colorimetry

Thanks again.


Don’t shout plz… :wink:
Roel is right imo, people who read somewhere an article about RT and tumble on the site upon your article, may not know who you are. I suggest to add a line with Pat David/pixls.us/gimp/trying to revive RT, something like that.

I was joking around. :slight_smile:
I’ll add a line to the beginning of the article as you’ve mentioned.

I’ve made the change as you’ve requested in this post above but I haven’t done a section specifically about HDR-SDR as you mention here.

I still think it would make a better follow-up post but I’ll defer to everyone here.

How are we feeling about publishing this? Can I get an affirmative from @Lawrence37, @Thanatomanic?

@patdavid I’m guilty of scanning this post so I may have missed it but you mentioned catching up on things…wrt the local adjustments I think @Andy_Astbury1 made at least one video that I recall watching and it was fantastic…really thorough about specifying the and managing the selection regions…it may have advanced past that since he made this some time ago… but it would be a good primer to save you some time…

EDIT Having said that nothing beats mucking around to get a real feel for what can be done and how to best explain it…

1 Like

Hi @patdavid. I’m happy with the post content-wise. Of course, there is a lot more that can be said, but in my opinion, the objective of the post should be to give an overview of the progress since version 5.8. I have read the draft many times already and I fear my brain is starting to fill in the holes. We could benefit from a fresh pair of eyes, e.g. Roel, so I’ll wait for his input. Then one last proofread. Speaking of proofreading, “It includes and Advanced mode” should be “It includes an Advanced mode”.

1 Like

I’ve just pushed my changes to the introduction, please take a look and feel free to undo changes if my style differs too much from your own!

I changed this. The rest of the text is fine as it is.

As far as I am concerned, we can publish the post!

1 Like


I think there is a small misunderstanding in the second link you note. I am not asking for it to be included in Pat’s excellent text at all, but it is a summary for those who want to read it, of the chapter “HDR to SDR…etc”, with comments that are also in the documentation. It’s kind of a short summary, to avoid reading everything.

Maybe I should have put @patdavid and others at the top of the post, or nothing

Excuse me for this misunderstood.

But for me your text is excellent and must be published as it is.

Thank you again.


1 Like

@patdavid @Thanatomanic
I reviewed the edits Roel made. The post has my approval.


That’s what I do!


@patdavid Here’s a little patch with two or three typo corrections. The rest are only whitespace fixes, unless they were intended to express something.

notdead.patch (21.1 KB)


Hello Pat, you wrote a very instructive article, my compliments.

One question though. It was my understanding that the spot removal tool was developed by @agriggio for Art and that it was implemented later in RT.
I’m wrong perhaps?

The tool existed first in a RT fork and was programmed by a gentleman named Frisch I think. Alberto merged it into ART and improved it.

Correct. Btw the original author is also known as @Hombre around here…

Okay, thanks for the explanation. So it was @Hombre who made that.