white render in standard camera

[kevin miller]

Hello, I am trying out vray (i use MR) and I am following vizmasters tutorials. One of the things I find annoying is that if you use a vray camera, you are always having to use that camera to get a decent test render. I would like to use the standard camera so that I can still get decent test render light in perspective viewport as I am working. When I try to render in perspectrive or a standard camera, the whole view comes out completely white. If I turn of the vray sun, it does the same thing. It does this if I turn on the vray sun or turn it off. However, it renders perfect in a vray camera. I adjusted the vray sun multiplier but still all white render in standard camera. What gives?

[aristocratic3d]

Can you please mention that are there any other light source in the scene? If so then divide their multiplier with 30.

[kevin miller]

There are no other lights that I am aware of. I unchecked default lights in vray plus I deleted my sun and I still get a completely white render in any view but vray camera.

[aristocratic3d]

Can you please post here the scene. I would love to take a look at that.

[Crazy Homeless Guy]

Can you please post here the scene. I would love to take a look at that.

 

If you are using a sun and sky system then you need to use a camera with exposure. Mental Ray controls exposure at the environment level, Vray controls exposure at the camera level. They both have advantages in different situations.

 

You can set you sun intensity value to something like .01 or .002 (I can't remember which) and then render with a standard camera or perspective. The only problem is that you will not have have white point correction is is necessary if you are using a sun and sky system. If you are not using a sun and sky system, then both white point and exposure really aren't that necessary, and can actually hold you back in producing quality renders.

[kevin miller]

I figured it out. Whenever I was setting up a vraysun, I was allowing it to set up the vraysky in the enviroment. It was not unitl I set up a very basic scene and rotated the cube around that I saw it was indeed an overexposure problem. I turned off the environment, dialed back the sn intensity multiplier to .001, and things were getting closer to normal.

 

CrazyHomeless Guy, the problem I have with your comment is that I am looking at two very good renders, one from 3Dats and the vismaster tutorial and one from Chris Nichols and his environment lighting tutorial. Both look extremely good and the light rig was a vray sun rendered with a standard camera. No sun/ skylight system and/ or vray camera used. I am talking very, very, good renderings. Now I know what you are saying about the great camera settings and such on the vray camera which is indeed nice but I wanted to know why I could not get the same effect as the tutorials. I was getting this totally blown out image. It still isn't good and when I follow the vismaster tutorial where you insert a vray sunlight, accept the vrayskymap, position everything, dial back the intensity multiplier, I get a blown out image unless I turn off the vray sky where they got a half decent render to work with. I'll use the vray camera for now but I am missing something on this tutorial or not getting a correct setting to render through a standard camera. Thanks for the help. Like everything else I just need to keep playing with things.

[Crazy Homeless Guy]

one from 3Dats and the vismaster tutorial and one from Chris Nichols and his environment lighting tutorial. Both look extremely good and the light rig was a vray sun rendered with a standard camera. No sun/ skylight system and/ or vray camera used.

 

Can you link to the tutorials?

 

I'm not really sure what was wrong with my comments compared to what you did...

 

Comment 1: If you are using a Sun and Sky system, then you need camera exposure. This is a fact, unless you dial back the intensity.

 

Comment 2: If you dial back the intensity, you will be able to render with a standard camera. Setting the sun to .001 was dialing back the intensity.

 

Comment 3: Unless you are using a Vray Sun and Sky system, exposure and white balance aren't really necessary. Even when dialing back the sun to .001, so that you don't need exposure, there is a high probability that the white values of the image will be off, especially if you are using a Vray Sky with the Vray Sun.

 

If you are using other methods for generating the skylight, then you can control the white balance through the color of the light, or the tone of the HDRI, hence no need for white balance.

 

Anyway, I would be interested in seeing the links, I like to see new techniques. The last Nichols tutorial I saw he was using a Vray Light set to sphere, and not a Vray Sun for the sun. That was a very old tutorial though. Circa 2005 or so.

Edited May 8, 2010 by Crazy Homeless Guy

[kevin miller]

I cannot make a link to the tutorials since they were DVD's. Since I am new to vray I am trying to find ways to learn the details but there is a good bit to understand.

 

I was not being critical of your comments at all. Being a newbie at this gives me no room to say much of anything. I think I may have misinterpreted what you were saying.

 

Anyway, I have much to learn.