Jump to content

Vray Light Noise near Objects


Marco Manunta
 Share

Recommended Posts

hi there,

 

i'm pretty experienced in renderings without artificial lighting, but now i've to render an interior image with some lamps and i ve got a lot of troubles.

 

as you can see on the image, i ve a lot of noise where the lights are near the object (in this case the columns, but i've got also IES light in other scenes with the same problem).

 

29nuyj7.jpg

 

what i have :

- Irradiance map + light cache - Dome light with cloudy hdri - some vray lights (just planes, even the round lights near the wall, are small planes)

 

what i tried to do:

- Increase shadow subdivisions of all the lights until 220 subdivisions (!!!) = no solution.

- Increase the subdivision of the irradiance map from 50 to 80/100 = no solution.

- Delete any bump map on the wall = no solution

- Increase Light cache samples = no solution

 

......help me please! :)

Link to comment
Share on other sites

  • 2 weeks later...

I find that vray plane lights are one of the nosiest options. Keep upping the shadow subdivisions until they clean up and like you did lower the noise threshold. The tricky part about upping the Adaptive AA filter is that it cuts the subdivisions down but I wouldn't be working with less than 1-12 anyways.

 

I find that IES are noticeably cleaner than planes, they usually only need 64 subdivs to be smooth as butter. It seems strange but that has been my experience. I try to use IES as much as possible and let the HDRI do as much of the lighting as possible.

Link to comment
Share on other sites

Yea I ran into that the other day kept forgetting to respond. Not sure what exactly that option does but I remember some talk on the chaos group forums about it needing some tweeks. In my situation I had half my room lit very smooth and then instanced the same lights to the other side of the room and it was horrible. Must have messed with it for 1/2 hour and then unchecked that and it was smooth again.

Link to comment
Share on other sites

My guess is the HDRI. I know everyone is a big fan of this lighting these days and as well they should, but there are a lot of them out there that create more noise issues than is worth it.

 

To Solve, I would try uping the subdivs here. Try boosting its intensity using Skylight portals and if all else fails, duplicate this map into the override slot and juice the GI to 1.5 or so.

 

My thinking is that if your problem is in the shadow and boosting the setting on the specific light is not the problem per se, then the problem is the GI. Remember that light is from a source, but shadow is too. Shadows are lit by the weaker GI light and with interiors, bounce light is typically an issue.

 

Probabilistic Lights is a setting for scenes with a lot of lights and allows VRay to select at random the amount of lights that get sampled in order to speed up the render time. The assumption is that in a scene with SO many lights, things are covered with light in excess of what is necessary and the random reduction helps speed things up, but runs the risk of adding noise. It also runs the possibility of saving on noise. The whole concept is scene dependent.

 

This tick box may fix things, but it isn't a guarantee. Your scene doesn't appear to have too many lights so I think the HDRI is your source problem. If you want to test the root, try adding a light select for each light in the scene an then use the Vray Frame Buffer and look at the passes. Your root will reveal itself. Even if I am wrong, you will know which is the problem.

 

Good Luck!

Link to comment
Share on other sites

Guest dialog
my problem is fixed when unchecking probabilistic lights in the global switches. thanks

 

when I first started using 3.0 I had the same heavy noise issues when using large amounts of lights...took a bit to figure out what the issue was

Link to comment
Share on other sites

  • 2 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...