Depth of field tutorials?

[Jimmy Alenius]

Hi! I have just moved from Mental Ray to V-Ray and have to say that it have been a very smooth changeover. Everything seems to work work right out of the box.
Now I have got to the DOF (Depth of field) and can't really get the hang of it. There's lot of tutorials for different sides of V-Ray but none really great about DOF. Or?
One negative thing about V-Ray is maybe the tutorial that I feel have very little examples. Meybe I'm looking at the wrong place?

Regards / Jimmy

[rivoli]

there's very little which is specific to vray as long as dof goes. the vray phys camera works pretty much like a real one in this respect, you can approach it as if you were taking a picture in real life. one thing to keep in mind is that the objects in scene have to be modelled and scaled consistently with their actual counterpart, otherwise you won't get the results you expect.

[Jimmy Alenius]

Hi Rivoli and thanks for a fast answer! Yes, it seems that it is very much like traditional photography. If I want to have more depth of field I need a smaller f-stop value and compensate with the ISO value, right? I don't use max exposure controll?

Btw, how do I get rid of the noice without getting to long rendering time? We're mainly doing animations so we have to keep the rendering times as low as they can...

Regards / Jimmy

[rivoli]

If I want to have more depth of field I need a smaller f-stop value and compensate with the ISO value, right? I don't use max exposure controll?

yes, as you say. with small values you get much depth of filed, while, of course, bigger ones give you a shallower dof. in case of stills you can compensate either with exposure times or iso values, they are redundant (even though I find iso much more comfortable to tweak).

Btw, how do I get rid of the noice without getting to long rendering time? We're mainly doing animations so we have to keep the rendering times as low as they can...

well, this might be tricky. the best way I know to deal with dof noise is raising the camera subdivisions. but for animations I wouldn't mind too much, with moving things/cameras and a blurring filter you shouldn't notice too much. one thing that may help is unchecking time independent in the dmc sampler rollout, this way you won't get static noise, but it will change over frames like on actual film.