Help: White Splotches in Render
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So these white splotches have cropped up in my renderings. The surfaces in the affected areas are connected and shouldn't be leaking light, so I'm not sure what's causing the artifacts. Attached are the settings used for the render -- any thoughts?
V-Ray 2.0 / SketchUp Pro 2016.
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Bad sampling issue. Noise threshold should be around 0.008 or lower, like 0.005.
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You could lower your noise threshold a bit, but you global subdivs multiplier is 2, so .008 would give you a .004 at render time...but anti-aliasing (image sampler) isn't what is causing the 'white splotches' in your render (we in the biz call them 'light leaks', btw). That would usually come from having your light cache set too low...although It doesn't look like you included light cache setting in you screen grab. Many factors come into play, but for interiors a light cache of 1500-2000 is a good starting point.
Honestly, unless you are a real Vray power user, I would recommend loading the vray defaults and starting over. Too many of your setting don't make any sense.
Here are a few things to look at:
Why did you change your max tree depth & face level/coef?
Does your dynamic memory limit really need to be 400? Do you only have 1GB of ram? If your scene is taking a long time to parse....this may be why. If you have a normal amount of ram...16GB or 32GB..go ahead and give yourself some more to play with...say 8 gigs or more.Adpative Subdiv? If you're using any blurry effects or have a lot of detail and textures then Adpative DMC could work better.
Filter - Catmull-rom? Maybe try Lanczos or good ole area...could give you better results.
Color mapping....your settings are kind of crazy. If you are shooting for a linear workflow you may have missed the mark here. Unless you have some reason for this....let me know - I could give pointers on a better gamma workflow. But, if its working for ya...go for it.
Indirect Illumination - why is your contrast base turned up to 1? Why is your primary bounce turned up to 1.25, but your secondary is turned down to .75? I've heard of plenty of people turning their secondary down to .8, but for and interior where you're are trying to get as much light bouncing around as possible, I'm not seeing the point.
Irradiance map & Light Cache - this is where I see your render suffering the most.
Irradiance Map - Maybe try bringing your max rate to -1 and bump your HSph subdivs up to 100 or 120, or higher...whatever it takes to smooth out the blotchiness. Play around the interp samples - try 30...but this depends on whats in your scene and how you would like it to look...20-25 could be fine. Why normal threshold to .1?
Again, unless you really know what you are doing and have reasons for the these settings, I would start over with the defaults. A lot of the vray setting are pretty good to start with, then you just tweak a few things and work on quality through subdivs settings. For vray its a good rule of thumb that if you don't know what it does, you probably don't need to change it. (of course, that's how you learn what it does, right
Long story short - turn up your light cache & irradiance map. Hope this helps!
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When I got blotches I tweak 3 things.
Decrease the noise treshold in the DMC sampler
Increase the HSph. subdivs in the irridiance map (to 100)
Increase the Interp. samples in the irridiance map (to 50)The rendertime will increase, but the blotches will be gone
You can experiment with the settings... -
try to increase your IrradianceMap "max rate" to something like -1 and see if that's enough..
maybe if this is noth enough try to raise it to 0 or also 1.. (this is just for such low resolution you are rendering at, you may drop this value down and try a bigger resolution)btw why did you change multipliers for primary/secondary bounces?!?
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@koenvdw said:
Increase the Interp. samples in the irridiance map (to 50)
i would not suggest to go that high with interpolation.. this can raise render time significantly and blur every detail in gi.. use with care!
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