Alpha Tonal Curve Adjustment

This came up in a Facebook discussion. If users are making stamps from greyscale heightmaps captured within Nomad, it might be helpful to be able to edit the tonal curve within Nomad rather than have to edit that image in something like Procreate or Clip Studio Paint and reimport. The idea would be to be able to chose an alpha in Nomad, call up an adjustable tonal curve graph, adjust the curve, ideally with an image feedback preview, then save a copy of that new alpha.


Isn’t that what the brush intensity slider currently does, without the need to edit the alpha? I presume that the current height map feature is giving the whole gradient height range of black to white so I’m not sure what else can be tweaked to make the alpha better? If you export the alpha with transparent background then the resultant stamp can be pulled to change coverage area & then the intensity slider can be used to change the stamp height on the fly.

Bezzo, what if you wanted to alter the gradation ramp and not have it linear? Oh well, just an idea.

Wouldn’t that alter the way the alpha works? Not sure I understand what you’re trying to achieve - make the white whiter or the black blacker?We can change the falloff in the stroke settings so you could control peaks & troughs in there maybe, but I think either way it leads to unpredictable results??

I think that’s what adjusting the alpha itself would fix; the results would be more predictable. Seems like a useful request to me.

I suppose I don’t really understand how altering the Alpha is different from applying it with different intensity?

@Bezzo By adjusting the alpha with a curve, you can change focus on more white areas or more black. One can even get detail which would not be shown else. Play with curve adjustment and you’ll see that you can do anything, from exposure to contrast pure black & white with curve adjustment.
But you know all that, don’t you?
This makes it possible to get a rich variety out of one alpha.
I made an example. First is original.

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Thanks man, I guess I was just thinking that all alphas usefully contain the full spectrum of depth from black to white & that seemed like enough for me. I hadn’t really thought about tightening the curves / levels to alter the alpha and make it do different things when applying to a sculpt. Not something I’ve ever consciously done but I’ve definitely done it heaps of times to get desired results & therefore can see that this would be a good feature inside of Nomad (although Procreate is just a click away). Maybe a panel within post process could be used to apply to height map renders - or maybe a curves / levels slider within the stroke settings?
Thanks for educating me guys - shows that you CAN teach and old dog new tricks :smiley:

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Infinite Painter offers a curve for the brush head (shape source in Procreate) and for the texture (Grain in Procreate) It can be very helpful. But only with visual feedback.
The true magic of Infinite Painter is that you can do a stroke, hold till quick shape, AND now you can change anything with real-time preview until you confirm the quickshape. That is where the real fun starts. Brush size, strength and even brush head curve and all the other brush settings can be changed with real-time feedback. Change spacing, rotate head or change completely to another brush.

Oh man, how much I would love to see this in Nomad! Infinite Painter is best app for this task.
And adjusting a curve is truly super powerful with real-time feedback on canvas / model!

I made a video for creating a Forrest quickly with those options, like size profile curve over brush stroke etc. Have a look and imagine this magic in Nomad…I am wet already :rofl:
I used the path tool, not quick shape but it doesn’t matter.

Watch out for the stamp. Stamp and move, stamp and move…there is nothing better except one could move complete path at once.
Stamp, quickshape path, circle, square, all this works with masks as well, and with lazy mouse. Procreate is a lame duck compared to this tool set, but has better memory management.