How to change GAMMA of an bitmap picture?

[BenediZ]

Hello,

How is it possible to change the gamma input of an bitmap?

(sRGB should be 2.2 and HDRI to 1.0 etc.)

I can't find any option...

Thanks

[10DSpace]

When you load a bitmap into a material slot like diffuse, specular..etc, in the lower left of the load bitmap dialogue is a gamma override option. Select the override instead of the default of Automatic and you change gamma to what you want.

[BenediZ]

Thanks, it means "override" is the "gamma" value, right?

So I can access it only, when I reopen the image (I have searched before only in the panel).

[10DSpace · Accepted solution]

@BenediZ 

Thanks, it means "override" is the "gamma" value, right?

Yes.  as soon as you click Override, the entry box to it's right let's you set the gamma to any value you want.  Default  value is 1.0.   see below: 

So I can access it only, when I reopen the image (I have searched before only in the panel).

Yes, when you reload the image and set it to  1.0 or any other value you want, Max will remember the setting.   

The only issue I am aware of is with the Multi-tile map which doesn't seem to remember or even actually change the gamma setting. See this link for more details if you are interested: https://forums.autodesk.com/t5/3ds-max-forum/multitile-map-does-not-support-gamma-override/td-p/9057...

Hope this answers your questions.

[BenediZ]

Hi,

I have realized, that there is an input and an output Gamma.

So I understood, that I can override the Gamma in the Bitmap nodes (and set the default in the Preferences at "Gamma and LUT"

But where is defined the output Gamma?

I have always thought, that in a linear workflow output is anyway always gamma 1.0

But I get this message, when opening a bit older files from others:

Thanks for help

[10DSpace]

@BenediZ 

The attached video in the first 6 minutes does a very good job of explaining how Max handles the management of input and output gamma under the hood.    

https://www.youtube.com/watch?v=iSwnXjADO9U

Regarding the File mismatch dialogue you sometimes get for older files (particularly if I did not create these files), generally, I  choose to Keep the System's gamma and LUT settings under the premise that I have set up the gamma display the way I want it and I want to let Max do it's thing as explained in the video.