Matching Photoshop and Max RGB colors

[3ddesign]

I've been wondering lately about why Max displays RGB colors differently than other Windows programs. This came up recently when trying to match Pantone color 4545 C which is the same as RGB 213 203 159. In this simplified version of the problem I created a texture in Photoshop with RGB 213 203 159. As you can see it looks the same across many different windows programs.



But if I create a material in Max with RGB 213 203 159 it doesn't match, apparently because of the way Max deals with gamma (?).



In this example I can easily work around the issue by simply using the Material Editor's eye dropper and select the darker teapot with the Pantone texture but in day to day work it is a pain having to create a Photoshop texture with the correct RGB, map it to an object then use that to obtain the appropriate RGB in Max.

I'm sure there is an easier way and I'm just too dense to figure it out.

Craig

[plastic_]

i guess it's more about how photoshop handles colors, since max is not color managed, so it ignores icc profiles. you may try to use the monitor display profile in photoshop to match the colors to max.

[3ddesign]

ICC profiling is completely irrelevant to the issue since I purposely (for this example anyway) used unmanaged files. The issue is how Max displays RGB colors and the way every other program I've tested displays them. I've examined many graphics programs and only 3DS Max displays RGB colors (seemingly) incorrectly and changing Max gamma settings doesn't help. I've searched this forum (although I have to admit, I'm not very savvy at searching) and haven't found anyone addressing this issue outside of LWF which, from what I could discern, didn't answer my questions.

Craig

[MoonDoggie]

You have "Affect Color Sliders" off, which won't actually keep them the same visually, it just won't show you. Check Affect Color Sliders to see the actual color you are selecting. iirc of course.

[3ddesign]

If you select Affect Color Sliders all that does is show you what Max will actually render. I unticked it to show what the color was "supposed" to look like.

I'm really surprised that so far no one has been able to explain why the colors in Max are different and more importantly how to get them to match. Is it impossible? Is Max that stupid or am I? I'm guessing its me for surely a software package that costs as much as Max couldn't possible overlook something so obvious and so important.

[MoonDoggie]

What I'm saying is if gamma is being used, it corrects the color _regardless_ of what the color slider looks like. If affect colors is unchecked It will still correct the color to the gamma adjusted color, you just won't be able to pick the color on the slider and know what it will look like.

You want to do the color:
RGB 213 203 159

Instead of just using the color on the material,

The order is important
1. apply a VRayColor map to the diffuse.
2. Set "Gamma Correction" to "none" (default)
3. paste in your pantone (RGB 213 203 159) in the VRayColor color
4. set "Gamma Correction" to "Specify"
5. set your gamma to 2.2

Now they should match. Yes?

[3ddesign]

Found my answer. When using gamma 2.2 correction in Max, RGB values in the Material Editor return a different color than the same values do in Photoshop (and most other windows programs). The solution was found here:
http://www.workshop.mintviz.com/tuto...odesk-3ds-max/

Now when using the color selector I highlight the field, hit Ctl+n, type in the expression below, enter the RGB value in the OLD field and hit "Paste."

255*((OLD/255)^2.2)

Once I type the equation into the calculator it stays so I don't have to retype it each time.

Not the most elegant solution but better than having to import a Photoshop texture just to get the correct RGB values.

Craig

[3ddesign]

Now they should match. Yes?

I tried that before hoping it would work but it has no effect. But the solution I found does the trick.

Craig

[MoonDoggie]

It should. The order which you paste in your RGB color and whether you have "Specify" or "None" selected is important, but I don't remember which way is correct, so I just paste it in each til I see which looks more correct.

[3ddesign]

You're right. I wasn't clicking Show Shaded Material in Viewport. Plus, I had to use1.0 as the gamma value. Now it works.

BUT... I have to mention that I found an even cooler way. The link I posted above also links to a plugin called the CoolPicker. I'm using it right now and it is the coolest thing since sliced bread! The best part is being able to click and drag anywhere on my screen and pick up the color. Also being able to use Lab colors is great since that is how my spectrocolorimeter reports colors. Don't know why ADesk doesn't pick this one up. It's been around since Max 1 or something.

Craig

[MoonDoggie]

Nice find! Post a link if you don't mind.

[particlerealities]

If you have dual monitors, it's helpful to have Photoshop open on one screen and Max on the other. Enter the appropriate RGB color values into the Photoshop color picker. Select the Max material you wish to have the same color, click on the diffuse color swatch to open the Max Color Picker, select the eye dropper then move the cursor over to the Photoshop swatch and click the color - this will change the Max swatch to the correct color with one click.

[3ddesign]

Amazing! You don't know how many times I wished Max would do that. Everytime I tried, I saw that I lost the eye-dropper cursor and assumed it wouldn't work. You'd think I would have gone ahead and clicked anyway to see what happened. Doh.

-C

[3ddesign]

Nice find! Post a link if you don't mind.

The link to the tutorial:

http://www.workshop.mintviz.com/tuto...odesk-3ds-max/

and the link to the plugin:

http://www.maxplugins.de/max2012.php...h=&sort=Author

Search on CoolPicker. Once the file is put in the plugins folder you have to go to Max > Customize > Preferences and in the General Tab under the UI Display group select the CoolPicker Color Selector.

Craig

[glorybound]

Nice! I'm working with a client, who is very literal. I'm doing an overcast, avoiding shadows, and the above mentioned color picker. It works well, except for very light colors. With very light colors, I get white.