Bug Image Alpha changes disproportionately

Hi there!

I have an odd behaviour when change the alpha of the images. I thought the alpha is calculated proportionally from 0 to 255, where 255 is 100%. But it's not so.

For example, I want to set alpha to 80%. There are results from Photoshop and Unity:



I tested in:

• 2022.3.8f1
• 2022.3.7f1
• 2022.3.4f1

— The result is the same.

Also I have Unity v2020.3.24f1 and it hasn't such problem

 

Color() accepts channel params from 0.0f to 1.0f

Color32() accepts channel params from 0 to 255

More on Color vs Color32, lossless, comparisons, etc.

https://forum.unity.com/threads/color32-should-have-an-method.1323399/#post-8367126

 

I create a default UI Image and change the Alpha from the Inspector.

 

So, anybody from the Support?