2 questions regarding Vray rendering (weird aliasing)

[fashlof]

So I've tried to get rid of 2 problems in my render. The first problem is found on the right side of the image at the door and window. I'm getting some weird aliasing that I can't seem to get rid of, and I have no idea why it' there or what is is - hence why I can't search for anything to fix the problem.

 

my other problem is that my picture gets super grainy in the back of the image. How can I fix that?

[salvador]

Post your settings. Hard to tell without knowing how it is inside. Looks like you are using Catmull-Rom. Try area instead. Rendering against super bright light like the environment outside the windows will tend to lead into this result.

[fashlof]

Sorry, here you go. I'm using Sincfilter. So how do I work around that?

[Ismael]

http://www.vray.us/vray_tutorials/rendering_vray_interior_tutorial.shtml

http://www.aleso3d.com/blog/?p=959

http://forums.cgarchitect.com/22345-noise-vray-images-2.html

[salvador]

Your have high settings here. I'd lower the DMC sampler Noise Treshold to 0.002 and I dont se the need to have "4" in the global subdiv. multiplier. Try a smooth AA filter or no filter at all; you can sharpen later in PS. Try rendering to a black background and see what happens.

 

It's probably not much but I hope it helps.

[Bruce Hart]

This may be because there is a big difference between the float value of light intensity from the outside compared to the inside. Right click in the image in the VFB to compare these values. You could try to turn clamp output on under the colour mapping rollout and perhaps sub-pixel mapping as well. As mentioned the type of AA filters can contribute to this problem

[fashlof]

Thanks so much for the help so far guys! I had some other stuff coming up so thats why it took me a few days writing back.

 

The problem with the jagged edges in the direct light was fixed by changing to exponential and ticking the sub-pixelmapping and clamp output.

 

So this my current scene is as follows: I got a vraysun and 2 lightplane. one at the door and one at the window. The image is still quite dark on the right side, would you recommend me to turn up the light planes or the sun a bit more? or adjust the camera settings (iso/shutter speed instead?)

[salvador]

In real life photography I would tweak the camera, but more important, I'd turn on the lights inside (even if it's day time) and I'd put another fill light right behind the camera (this one with low intensity)

[fashlof]

Allright. I don't know if it's a dumb idea but I've always thought of the photometric light as one of the last things to put in the scene?

[salvador]

Try with VRay IES lights. You can use them with a variety of IES files; from wide open to tight direct. IES files are not hard to come by in internet. ERCO, for instance, has a bundle of them and they are free. You can adjust color / temperature, intensity, etc. And they are fully VRay compatible (as they are supposed to be).