Shalinar 2 Posted March 21, 2017 (edited) Hi everyone, I've noticed an issue shining a light through a refractive material. The refractions don't seem to be energy conserving. Using a point light with intensity 1, exposure 0, no attenuation, shining through a grid with a basic mantra surface material with refractions enabled, the brightness values of the resulting pixels in the render are extremely high. Some are as high as 4,000. Why is this? In this thread, Symek mentions that the BSDF model is not inherently energy conserving, so it would have to be applied post-process. Seems odd that this wouldn't already be done in SideFX's shaders... If that's the case, though, how can I make refractions in the mantra surface shader energy conserving? Thanks, Chris EDIT: Forgot to upload sample scene, here it is light_refraction_broken.hip Edited March 21, 2017 by Shalinar Share this post Link to post Share on other sites
Guest tar Posted March 21, 2017 not sure as your file isn't working in H16 - there is a conserve vop that you can add to the shader, or maybe try H16 as it might have updated shaders. Share this post Link to post Share on other sites
Shalinar 2 Posted March 21, 2017 13 hours ago, marty said: not sure as your file isn't working in H16 - there is a conserve vop that you can add to the shader, or maybe try H16 as it might have updated shaders. Yeah sorry I should have mentioned this is an H15.5 job.. I'll look into the conserve vop, thanks Share this post Link to post Share on other sites