Question to V-Ray

[gnassbasti]

Hi ! Im new to V-Ray and am getting along bit by bit. I have read the help and the set up tutorial, and rendered an Image which Ihad rendered before with mental ray.

The set Up which I have used is:
- Adaptive DMC as sampler,
- AA filter is Area (1.5).
- Color Mapping is intensity exponential
- Gamma 2.2
- Dont Affect colors
-Linear Workflow on
- Primary bounce is Irradiance map (set to High)
- second bounce is Light Cache
- I rendered it out as an EXR
- I changed the EXR in Photoshop to a JPG without changing the gamma or exposure

Here is the result:

http://img822.imageshack.us/img822/5...ghtingvray.jpg


Here is what I run into:

1. The indirect illumination ist still way too dark. How do I get it brighter? If I increase the light's intensity, it will just create blown out areas.
Do I need to fix some thing is Photoshop or is there a renderoption?

2. As you can see, the shadow and reflective areas are all very grainy. I thought it was the shadow rays of the directional light I'm using, but increasing them or the Ray depth limit doesnt change much at all. Is there a render setting that I need to change?

3. The Shelves on the wall are kind of weird. It looks like AA issue, but where di I change it?

I hope someone can help me here!

[garage3d]

This is what I'd try. Just for the sake of tyring. It might be contrary to some theories since I'm not an expert, but it might work.


*Format: png 16 bit.
*AA: DMC 2/5 threshold .01
*color mapping: Exponential.
*uncheck Dont affect colors.
*Linear Workflow off
*gamma 1

environment Gi black

GI:

refractive causticss on

*primary IM
*secondary LC

multiplier of both 1.

and I'd start playing with some rect light in the windows.

try sharpening a bit your keylight shadows. If it is a sun light it probably has 8 levels of subdivisions. Set them to 25, and lower your Size multiplier. Its strange to have that unsharp shadows at that hour.

hope that gives you some light. get it? light

[snivlem]

Check out these first of all:

http://www.youtube.com/watch?v=ZURdN48My9I

Then more of his videos.

http://www.youtube.com/user/aweidenh.../5/ZURdN48My9I

Nederhorst settings are expensive though, I learnt these settings first then found ways to get the speed by learning what things do what and what settings you can afford to tweak (quality/speed).

One thing compared to mental ray, the settings are very "global" and "unified" it's important to understand that.

1. The indirect illumination ist still way too dark. How do I get it brighter? If I increase the light's intensity, it will just create blown out areas.
Do I need to fix some thing is Photoshop or is there a renderoption?

Don't increase the lights, set them to an appropriate real life value and instead increase the camera's ISO or make the shutter speed slower instead. This will brighten the image and look more natural than light burning.

2. As you can see, the shadow and reflective areas are all very grainy. I thought it was the shadow rays of the directional light I'm using, but increasing them or the Ray depth limit doesnt change much at all. Is there a render setting that I need to change?

I think it's acceptable for that resolution, maybe it is worse for you on higher res. In that case you could increase the subdivs on the material's reflection and the subdivs on the shadow....or you could globally increase the quality by lowering the DMC threshold like garage3d suggests (.010)

3. The Shelves on the wall are kind of weird. It looks like AA issue, but where di I change it?

It is strange. I haven't seen anything that bad before as everything else is quite nicely aliased. You could try "subpixel mapping", but that's usually a last option thing (for me anyway). I'm not sure what elsle you could try there.