If you are using 3ds max 2014 or newer, usually there is no need to alter any default gamma settings in Corona or 3ds Max as they are handled automatically. Make sure that in Rendering > Gamma/LUT Setup..."Enable Gamma/LUT Correction" is checked and Gamma is set to 2,2. In older versions of 3ds Max, altering the default settings may be necessary (see below).
1. Gamma and LUT settings in 3ds Max preferences
Correct gamma settings in 3ds Max 2014 or newer:
2. When saving rendered images
In 3ds Max 2014 or newer it is not required to alter any settings when saving any types of rendered images.
3. When loading bitmap textures
When loading ordinary bitmaps (for example into "diffuse" slot), you should always use "Automatic" gamma setting. When loading bump, displacement, or normal maps, it is correct to use gamma override of 1.0. You may also want to use gamma 1.0 for other grayscale textures, such as refraction level, reflectivity, opacity, etc., but this can be dependent on the kind of result you are seeking.
See also: How to use normal maps?
Below are two scripts which will force ALL 3ds Max Bitmaps or CoronaBitmaps to use automatic (or other, specified) gamma setting.
NOTE: This will alter all the textures in scene. Setting the gamma to "automatic", will also affect bump, displacement and gamma textures, which should be left at gamma 1.0. Setting the gamma to other than automatic, will also affect diffuse, and other textures, which should generally have gamma set to "automatic".
For native 3ds Max Bitmap node:
for tmap in (getClassInstances BitmapTexture) do
tmap.bitmap = openBitmap tmap.bitmap.filename gamma:#auto
for tmap in (getClassInstances CoronaBitmap) do
tmap.gamma = -1.0
4. Changing input and output gamma in 3ds Max 2014 and newer
Input and output gamma settings have been removed since 3ds Max 2014. This may sometimes cause problems as these settings may be altered in files saved in older versions of 3ds Max. To repair such scenes, please refer to this Audotesk article: Gamma Correction changes in 3ds Max
The .ini file should contain following lines:
You can also use this script to alter input and output gamma in 3ds Max: [ link ]
5. When loading scenes
When loading scenes saved with different gamma settings than currently used, 3ds Max will prompt whether the file's gamma settings should be adopted, or system settings should be kept. Always select the option giving you the correct gamma settings, meaning "use system settings" in most cases, provided that your 3ds Max gamma settings are configured based on this guide.