How do I convert/change only the hue of an image to a rainbow?

[Forkanion]

Let's say, I want to make an american dollar bill look rainbowy. I would take a spectrum rainbow the size of the dollar bill, layer it on top of the bill, and use multiply or overlay, but that changes the saturation and brightness of the colors of the bill instead of directly converting the entire bill's hue into a rainbow. The point is, I only want the hue of every pixel of the bill to change into a rainbow gradient, not the saturation and brightness. How do I do this?

Edited September 17, 2020 by Forkanion

[Ego Eram Reputo]

Hey there @Forkanion - Welcome to the forum

 

Conditional Hue & Saturation plugin is the answer.

 

 

To see how easy it is to do this type of effect, check out this post: https://forums.getpaint.net/topic/21134-how-can-i-create-a-shape-and-recolor-it/?do=findComment&comment=348884

[Ego Eram Reputo]

Using Fade Vertical instead of Fade Horizontal...

 

[Forkanion]

14 hours ago, Ego Eram Reputo said:

Hey there @Forkanion - Welcome to the forum

 

Conditional Hue & Saturation plugin is the answer.

 

 

To see how easy it is to do this type of effect, check out this post: https://forums.getpaint.net/topic/21134-how-can-i-create-a-shape-and-recolor-it/?do=findComment&comment=348884

Is there a version of this software (or even a way) to make it fade vertically? I tried angling the object to try and make the fade look diagonal when I angle it back to before, but that cuts out a good majority of the fade.