Announcement

Collapse
No announcement yet.

Irradiance Spots

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Irradiance Spots

    im having some hard time removing with some Irradiance spots. This problem i have had in a few differnt files. mostly the problem occurs when your camera moves inside some object so something where the normals are more or less pointing in inward towards one another.
    so the splotches seem like i get a random stray black irradiance particle surrounded by a bunch of light ones..

    so what i would be interested to figure out if there is some simple principle that I'm missing that's causing the stray spots that i can remove them more easily than increasing the inter.p samples(currently my interp samples are around 80 which maybe seems high? and cost alot of rendertime)
    increasing the subdivs seems to only put more resolution in the splotches so its still spotty but just "smooths the spots" if that makes any sense.

    my first hunch was the normal threshold because the spots seem to be happening in the corners and creases, if i lower the normal threshold it seems to make the splotches "smaller" but they are still there.(also huge increase in render time)

    the spots do become less noticeable in the final render if i use enough interp samples to smooth it out, where if i could just figure out why i get these splots in the first place maybe that would lead to be a better solution.
    i know its sort of hard to tell whats going on in just an image but to maybe someone has some clue how to control the spots?

    you can especially see the stay spot in the red circle? what is that black splot doing there???
    http://i245.photobucket.com/albums/g...ebb/Spots2.jpg

  • #2
    Hello, Bradon,
    you can have a try by increasing the "Min samples" value located in the "Vray : DMC sampler". for example 128. It helps to fight against black IM spots without impacting too much rendertimes.
    Jérôme Prévost.
    SolidRocks, the V-Ray Wizard.
    http://solidrocks.subburb.com

    Comment


    • #3
      wow that worked out REALLY really well. thanks for the tip. ill have to look into the reason why that worked and why i would not set that attr to be 124 as a DEFAULT?

      Comment


      • #4
        cool ! it saves my life some years ago..

        How big was the impact on your rendertime ?
        Jérôme Prévost.
        SolidRocks, the V-Ray Wizard.
        http://solidrocks.subburb.com

        Comment


        • #5
          why ? because each Irrmap Hsph that have been managed by the adaptive sampler (0.85 = 85% of you irrmap !) is now forced to fire 128 samples before being aborted by the early termination process, even if the noise thresold have been reached.
          In fact, whatever the noise thresold, each IM hsph is forced to take at least 128 samples. That's not happends often, that's why rendertime is not so much impacted, but avoids the risk to have IM samples computed with only 8 or 16 samples.
          Jérôme Prévost.
          SolidRocks, the V-Ray Wizard.
          http://solidrocks.subburb.com

          Comment


          • #6
            well its a bit hard to say because im rendering on a farm with different computers.. however all the nodes are the same procs. but i think changing that setting had ZERO increase on the render time.. possibly a few seconds SAVED if anything. AMAZING

            Comment


            • #7
              Héhéhé ! Many people consider that 128 is an incorrect value (too big). I always find that it helps to have a consistend IM, even at medium/low settings. this method is better than increasing Hsph subdivs to try to get rid of these black splotches !
              SolidRocks have received some critics about this crazy value, so i'm really happy that you find it useful
              Jérôme Prévost.
              SolidRocks, the V-Ray Wizard.
              http://solidrocks.subburb.com

              Comment

              Working...
              X