Photoshop - grayscale colors as INDEX not PERCENTAGE

Started by N-drju, May 20, 2018, 03:37:16 pm

Previous topic - Next topic

N-drju

I am at a loss trying to figure out how to switch color units in grayscale images from percentage values into index (0-255) values in Photoshop...

Mind you - I don't want to change a picture into indexed color. Don't confuse it.

The thing is, I need all, 256 shades of gray to operate on. However, when I use grayscale palette in my image, the colors are rounded up into these fucking percents... which accounts for an unacceptable loss of 2,55 color per one percent...

If you now how I can switch color unit display mode, I would sure appreciate...

[attachimg=1]
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

archonforest

I think it is not possible since it is grayscale. Since there is nothing to mix into that no other slider presents. Perhaps you can make the original image black and white?
Dell T5500 with Dual Hexa Xeon CPU 3Ghz, 32Gb ram, GTX 1080
Amiga 1200 8Mb ram, 8Gb ssd

N-drju

There is no "original" image. I need to sculpt one from scratch but have only 100 shades of gray instead of the 256 that are normally possible. Even when I enter, say, 33 for R, G and B it still reverts to the fucking percent value which badly modifies the RGB input.
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

Why don't you 'sculpt' in 16-bit greayscale tiff?

N-drju

Because I need 8-bit grayscale and regardless of what grayscale settings I use, I am stuck with percent values... :-[ Besides, I think there are going to be some artifacts or splotches as soon as I convert the image.
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

N-drju

Okay, one more puzzle - why for heaven's sake when I save a grayscale bmp file does it turn into an INDEXED bmp file upon reload?!! ::)
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

That puzzled me too, a while ago (and still). So I use tif.

N-drju

It's like you only have one shot at creating and instantly using the grayscale image, because the moment you close, it's all mess again. What kind of dimwit invented this? ::)

I wanted to have a go at a (rather unorthodox) trick, so 8-bit GS .bmp was what I aimed for and I don't think I could use .tiff. But maybe I can, and then convert it to grayscale...?

As long as .tiff to grayscale conversion doesn't destroy colors and turn smooth shades to dots... ::)
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Oshyan

TIFF can represent grayscale, just as BMP can. What is your intended end use? Why does it need to be a BMP?

- Oshyan

N-drju

Well, I've been asked by some guys to check custom terrain importation feature for a game they work on. The thing is this topo feature, for some reason, currently works only with 8-bit .bmp images. When I checked RGB-formatted files or .pngs, the terrain representation was indeed flawed.

It's no biggie, because the anticipated terrain size is small. So you can probably produce a terrain in one go, with a coffee break in between.

It's not the game's problem however! It's the problem of Photoshop and automatic conversion of GS image to indexed format!

In PS, you can freely edit grayscale images. BUT once it gets converted to index after save, you can't use filters, smudge, sponge or sharpen tools. FOR WHAT F### REASON may I ask?!
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune

Have you searched the web for answers to that F... question?

N-drju

I f### did indeed. :P There's not a single word about why does it happen. Lots of conversion tutorials but only about intentional conversions...
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"

Dune


N-drju

Ha, I somehow missed it out... it was buried.

That explains a lot.
"This year - a factory of semiconductors. Next year - a factory of whole conductors!"