I seem to be having problems with vray dirt map and LWF. My dirt segment (occluded color) is hardly noticable, the color is very faded, and the gradient is almost non existant. Does it have something to do with my gamma settings? Can it be overriden?
It’s definitely the gamma. When i turn it off, i’m able to achieve better results from the dirt map.
Is there a solution for this problem?
It might work if you use a vraycolour map in your occluded/unoccluded so you can change the gamma.
I usually put the whole thing within a colour correct though, or my bitmaps for occluded within one.
How do i change the gamma of the vray color?
change the RGB multiplier to 0.4545 if ur gamma is set to 2.2!
That made my white color grey… Arent you supposed to have white and black the same no matter which gamma is used?
just turn your gamma back to 1 and render a sepereate pass
“just”?
:lol:
This kinda makes vray dirt useless.
something doesn t sound right to me…
if ur 255,255,255 RGB renders grey then ur camera (i supose ur using vray physical cam ) needs to be set up correctly…
or turn it bak to 1 and turn off exposure on the camera settings
nonono, you didn’t read the whole thing. My white rendered grey after multiplying it by .45454, as someone suggested above.
I mean, i’ve know that it didn’t make any sense, but i gave it a shot and it made my white gray just as i thought it would happen.
I think i’ve managed to fix the whole gamma issue by using color correct to modify vraydirt map.
I have the same problem as you had earlier. I don´t get VrayDirt to work when I in LWF… What do you mean with color correction? Do you mean using VrayColor?
When I use VrayColor in the occluded color I get a very light gray result… I would like it black!
Seems not many people have problem with this… I mean with the big LWF-hype and all. : )
Can you not just use the colour correct plugin on it?
Hm, I’m afraid I don´t know what plugin you refer to… Is this something I have to install or is it installed with Vray?
You can get the colorcorrect plugin here…http://www.cuneytozdas.com/software/3dsmax/
As long as your using GI, you’ll almost never get the dirt/AO areas to be black since they are receiving bounced light as well, even more so if you are using LWF since that will push more light into the occluded areas. You can increase the effect by unchecking the “Ignore for GI” checkbox in the vraydirt material so that the GI will now see the dirt in the corners. I almost never make the occluded area anything but black (at leat for a normal AO effect) since it almost never goes completely black anyways and just serves to darken up the normal texture.
This problem is apparent in any procedural texture which utilizes gradation, even if it is being used as a bump or opacity map. It is actually a pretty good demonstration of what these LWF gamma settings are actually doing, pushing the default gamut closer to white. Currently the only solution I am aware of is the color correct plugin.
Ok… thank you for your replies! I installed the color correction plugin… what it does is it force a bitmap to look a certain way no mather what? My quick tests didn´t work very well, have to give it another shot…
Assuming you have your gamma setting in MAX preferences set to 2.2, you basically need to counteract this effect since the native functionalities of procedural textures are made to work in the default MAX envirionment (gamma correction disabled). The VRayDirt map is calculated mathematically within the program, therefore it is a procedural map.
To do this, you will embed the VRayDirt map in the ColorCorrect map and set the Gamma setting in the ColorCorrect map to 2.2. Bitmaps can be handled automatically if your MAX Gamma preferences “bitmap input” is set to 2.2, making the necessity of the ColorCorrect map strictly for procedural maps.
To illustrate the effect visually, this top image is how MAX would calculate a B/W gradient using default settings:
And with Gamma correction set to 2.2:
Notice how the gradient shifted to white, causing an unbalanced gradient, and in the end, and undesired effect. Using the ColorCorrect plugin will readjust the gradient to make it compatible with Gamma correction set to 2.2.
