Layer mode overlay formula is different from normal

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Layer mode overlay formula is different from normal

Postby com » 13 Jan 2020, 05:17

I want it to behave the same as photoshop. Is this a bug?

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u2bleank
 
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Joined: 11 Jun 2012, 10:41

Re: Layer mode overlay formula is different from normal

Postby u2bleank » 13 Jan 2020, 09:03

it should be the same ( do you have a sample ? )

The possible difference is the color space in which the Blending occur. Black Ink works in Linear Color space while Photoshop use the color space of the current document by default.
Image

com
 
Posts: 5
Joined: 13 Jan 2020, 05:11

Re: Layer mode overlay formula is different from normal

Postby com » 13 Jan 2020, 10:14

The color values ​​are clearly different.
My photoshop color space is linear.

For example, if you draw gray B (128,128,128) on gray A (128,128,128) in photoshop with overlay

The formula for photoshop is
1-2 * (1-0.5 (Gray A)) * (1-0.5 (Gray B))

The drawing result is
(128,128,128)

But

blackink drawing results
(119,119,119)

sample
https://15.gigafile.nu/0120-d41817fbd27 ... c7b6b5edd8

The same is true for hard lights, which are the inverse of calculations for overlays.

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u2bleank
 
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Joined: 11 Jun 2012, 10:41

Re: Layer mode overlay formula is different from normal

Postby u2bleank » 13 Jan 2020, 11:52

hum it's what I was explaining.
The Overlay equation take place in linear space and the 128 gray isn't 0.5 in linear but 0.21..
BUT we will make the overlay behave the same way as in Photoshop in the next update.

com
 
Posts: 5
Joined: 13 Jan 2020, 05:11

Re: Layer mode overlay formula is different from normal

Postby com » 13 Jan 2020, 13:03

Thank you!!!

cathiss47
 
Posts: 1
Joined: 09 Mar 2020, 13:17

Re: Layer mode overlay formula is different from normal

Postby cathiss47 » 09 Mar 2020, 13:19

u2bleank wrote:it should be the same ( do you have a sample ? )

The possible difference is the color space in which the Blending occur Rachat de crédit meilleurs taux. Black Ink works in Linear Color space while Photoshop use the color space of the current document by default.
Image

I didn't realize there was so much difference between image processing tools.


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