How to expand / squeeze a channel in an image editor?

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1

Hi, when I export a displacement map from ZBrush it looks like this. All the info is squeezed into this small spike in the graph. It equals 1 point of strength in the Blender Displacement modifier.
And I have a texture that uses the whole range of an .exr file, but because of it I am setting it to 0.001 strength of displacement. (exported from Substance Painter)
I want to combine two of these textures into channels in a single .exr file, but because they have different strength options the result doesn’t work.
How do I squeeze a channel 1000 times or expand it by the same number? I use PS, AP or Krita.

image
image1496Ă—1100 64 KB

I am not a professional in image editors, please help!

2

There seems to be some missconception… if your images does have only one value over the sepctrum… then this is essentially no map at all… it’s just all one single value… there is no difference and so no detail…

3

No, the map is fine, it’s an .exr file format and it renders perfectly well.

4

Not 100% sure but it seems your image in PS is set in 8bit, because the max output level is set to 255.

Did you try to save that image and use it as displace ? it’s possible that you loose some details…

I don’t know how to do that in these software, I’d try to use multiply and divide blending mode, crossing finger PS (or else) is set in linear and no extra cleverness mangles the data.
Since they are more photo / panting software than anything it’s not super reliable unless you are 100% sure of what you do.

I advice to do the same thing in blender / Nuke / Natron, as they are much more capable of dealing with linear data and data in general (data as opposed to images)

PS, AP and Krita are different software so you might get better luck with any of these, maybe krita, being younger handle that better…

Good luck !

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5

So then… as @sozap said… it’s maybe just a wrongly convertd import (8bit)…
.and usually some histogram strecth or level like you do show would be used to change this… (but in more than 8-bit)…

But you initial problem:

…might be not so easy to solve… maye i ask:

Why do you have two different maps with different “areas/intervals” where they do have their values… ??

6

One map I exported from Zbrush, and it always look like this, and it works well.
The other map is from Substance Painter.

7

Hmm… :thinking: …maybe there are any “stretching” factors in the first place ??

But usually this is normalising, contrast stretching… or histogram equalization… leveling (with white and black point setting…maybe auto)…