How to set up Heat Haze?

[KushKush]

Hello, I'm trying to set a heat haze in the scene (Mirage effect), I've tried several options but none seem to work. I've tried to create a heat haze cube to include in its radius both camera and the scene objects, I've tried to put a cube radius between the camera and scene objects, and I've tried to include scene objects within cube radius but leaving camera outside.
https://docs.chaos.com/display/VMAX/...llout-heatHaze Documentation seems to say something about "Gradient surface channel", what's that? I increased ground Vray mtl max depth from 8 to 20(refraction color 0 black), no change . Do I need to simulate something in Fumefx first? currently my volume grid has no input cache(empty).
I've quite confused.
Reference I'm aiming for: https://www.youtube.com/watch?v=-01sSjs132Y
Pictures below show result and vray volume grid current parameters

[hermit.crab]

When working with Volumetric Haze, the refraction ray is traced based on the information set in the Surface options (in other words it controls the "distortion"). The "gradient of the surface channel" refers to that.

You do not need a simulation to produce the haze effect since you can use "Textured" as the Surface mode. If you want it animated as in the reference video, you should animate the Surface texture.
A few things worth noting - the VolumeGrid should be in front of objects (since intersections may produce black artifacts) and the effect is very slow to render. Sample scene here. (thanks to georgi.zhekov).

[KushKush]

When working with Volumetric Haze, the refraction ray is traced based on the information set in the Surface options (in other words it controls the "distortion"). The "gradient of the surface channel" refers to that.

You do not need a simulation to produce the haze effect since you can use "Textured" as the Surface mode. If you want it animated as in the reference video, you should animate the Surface texture.
A few things worth noting - the VolumeGrid should be in front of objects (since intersections may produce black artifacts) and the effect is very slow to render. Sample scene here. (thanks to georgi.zhekov).

Thank you so much for answering and providing the file.
Is there a difference between doing distortion in 3ds max/vray or doing the distortion in "post"?
How does the Mirage effect created? Similar to documentation and the reference. In documentation, the slider indicates it as part of the effect.

[georgi.zhekov]

Hey,

The difference between doing it in 3dsMax or in another post-processing app is the amount of control that you wish to have. Doing it Max will give you better control on where and how the effect will look like, though it will be slower to render. My advice is that if you can get away with a solution in "post", do it in post and save on the render times
The image in the docs is created by loading a fire/smoke simulation in the VolumeGrid and using the Temperature channel for the distortion. The effect will rely on how large are the temperature values or in the case of the scene from the previous post, how stronger the noise texture values are. If you bump up the Output amount in the Output texture a lot - like 100 or 1000, this will distort the image more and will give you a different look.

[KushKush]

Hey,

The difference between doing it in 3dsMax or in another post-processing app is the amount of control that you wish to have. Doing it Max will give you better control on where and how the effect will look like, though it will be slower to render. My advice is that if you can get away with a solution in "post", do it in post and save on the render times
The image in the docs is created by loading a fire/smoke simulation in the VolumeGrid and using the Temperature channel for the distortion. The effect will rely on how large are the temperature values or in the case of the scene from the previous post, how stronger the noise texture values are. If you bump up the Output amount in the Output texture a lot - like 100 or 1000, this will distort the image more and will give you a different look.

Hi, thanks for answering and providing me with test file yesterday. I've just tested by loading cache of simple fire, I set surface to temperature but it does not seem to recreate that mirage- reflect distort effect, but rather another version of distort. Looking around google I found a mirage diagram that shows both cool and hot air, do I need to set cool and hot temperatures? I'm not sure I understood correctly. = [

[georgi.zhekov]

Ah, for the reflection at the bottom, you need a combination of a low angle of the camera and there must be a heat in the lower parts of the grid. I have made a sample scene and attached a simple cache file here - https://drive.google.com/file/d/1wmr...mgPOimRUV/view

[KushKush]

Ah, for the reflection at the bottom, you need a combination of a low angle of the camera and there must be a heat in the lower parts of the grid. I have made a sample scene and attached a simple cache file here - https://drive.google.com/file/d/1wmr...mgPOimRUV/view

Thank you, I had to download phoenix for some reason just to render the scene. If I understood correctly, there is a small rectangular in the lower section that has temperature of 400.

[georgi.zhekov]

Hmm, the scene should render correctly with the latest official V-Ray 5.2, no need for Phoenix, may be the cache file name mislead you. Yes in this example a small box emitting temperature was used to produce the cache.

[KushKush]

Hmm, the scene should render correctly with the latest official V-Ray 5.2, no need for Phoenix, may be the cache file name mislead you. Yes in this example a small box emitting temperature was used to produce the cache.

When I opened the scene it said something about Missing dll phoenix and when I tried to render the scene it showed black screen( calculating atmosphere). Never mind I opened the scene and now I'm trying to recreate the effect in fumefx.
Thanks for your help Georgi.Zhekov.