Sigmoid module advice and guidance needed

[Christian-B]

@jandren

Nice example gradients!

There is a very good reason for not having a “exposure slider” in the display transform. The whole scene referred workflow revolves around normalizing middle grey as 0.1845 instead of an arbitrary maximum value to one. This is why the sigmoid module works so well with the already existing scene referred modules! The whole sigmoid curve is actually pinned downed by the observation that middle grey (0.1845) should pass through this module unmodified. All other values on the curve are defined relative to that condition.

There was a slider for this in filmic, “middle grey” but it has been hidden for the same reason as it’s not included in the sigmoid module.

Hello,
Personally, I opted to fine-tune the black, white and mid-gray settings with the “RGB Levels” module.
To avoid making back and forth, would it not be possible to have a link of the slider of the exposure module.

Greetings from Brussels
Christian

[kofa (István Kovács)]

Changing the exposure potentially influences parametric masks, the tone equalizer’s masking settings, color balance rgb (which divides the image into shadows, mid tones and highlights, and has its own mask middle grey fulcrum, threshold white fulcrum and contrast grey fulcrum controls), and who knows what else. You can’t just wire all brightness-related controls back to exposure.

[Christian-B]

Hello,
You are right, that’s the reason why I added I slider of the mask exposure compensation, so I can adapt it when I change the exposure at the end of the processing

Greetings from Brussels
Christian

[Wkclethro]

Just a thought; have you considered a button or check box to max out the contrast so it is easy to set the exposure for the mid grey? Thanks for the hard work! Cheers.

[jandren (Jakob Andrén)]

Haven’t thought about it. Could be something! I’m expecting people to learn though and not need it as much after some time.

[Wkclethro]

It’s a tricky one, the processing should really start with taking the photo (correct exposure, framing an focus solves most problems) and an awareness that our visual system also does image processing that introduces its own artefacts.
Personally I like to try and understand as much of the process as I can, just makes it easier to get the image I intended; not a fan of the computer deciding what I want.
Thanks for your efforts!

[priort (Todd Prior)]

Depending on the images I may edit it but there is an autopicker in exposure and I set that to 50% … I will often try it on the whole image first just to see what it lands… if I don’t like that I will choose a subject or area… I find this is often all you need

[mikae1]

@Wkclethro

Just a thought; have you considered a button or check box to max out the contrast so it is easy to set the exposure for the mid grey?

A preset or style would do? That’s how I use it. Not sure a button would add anything.

[Wkclethro]

Good call, thank you.

[elstoc (Chris E)]

@jandren

Yes, I will supply the documentation asap!

The 4.2 release is fast approaching… any progress on this?

[jandren (Jakob Andrén)]

Working on it! And an answer to the white background image editing problem after that!

Expect a PR before the end of the week