Erik_JE Posted March 12, 2012 Share Posted March 12, 2012 I am mucking around with a small scene at home and having some trouble with getting the lighting right. If you see the picture I wan't to lit the scene with the lamp but it feels like the lamp shade "eats" too much light. I wonder if there is a way to specify how much light that should be let through when using subsurface scattering without the lampshade lighting up too bright. Been tweaking parameters all evening but can't seem to find the right one. Suggestions for parameters (mantra surface material), shader modifications that can be made or easy ways of cheating it are very welcome. Quote Link to comment Share on other sites More sharing options...
nord3d Posted March 13, 2012 Share Posted March 13, 2012 I am mucking around with a small scene at home and having some trouble with getting the lighting right. If you see the picture I wan't to lit the scene with the lamp but it feels like the lamp shade "eats" too much light. I wonder if there is a way to specify how much light that should be let through when using subsurface scattering without the lampshade lighting up too bright. Been tweaking parameters all evening but can't seem to find the right one. Suggestions for parameters (mantra surface material), shader modifications that can be made or easy ways of cheating it are very welcome. Hi. IMO, the picture looks too dark. Are you using gamma correction for rendered image (something like "2.2")? Quote Link to comment Share on other sites More sharing options...
J.Santos Posted March 13, 2012 Share Posted March 13, 2012 Hi Erik! Disregard my post if it doesn-t have anything to do but CmiVfx have a lesson that might be worth checking because of the similarity of scenes, approach to shader/render and faking/solving the question of the lamp shade! Good luck! Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 13, 2012 Author Share Posted March 13, 2012 (edited) Hi. IMO, the picture looks too dark. Are you using gamma correction for rendered image (something like "2.2")? Embarrassingly i had forgot to gamma correct. It made it a lot better. Next problem is to not get the whole shade to light up so much. Edited March 13, 2012 by Erik_JE Quote Link to comment Share on other sites More sharing options...
magneto Posted March 13, 2012 Share Posted March 13, 2012 I think the original looks better, dark and dramatic Quote Link to comment Share on other sites More sharing options...
zarti Posted March 13, 2012 Share Posted March 13, 2012 IMHO , the flatness and the ' absolutely-white ' lamp needs a bit of tweaking . it is not a source of light in itself so 'i cannot accept' ( so to speak =} ) .. its uniformity and intensity . maybe you can add a pale layer of diffusion on top of it .. also / maybe add some small details ( canvas texture , and some nonuniform-gradient thickness there .. 'where fabric meets the wire' ) p.s.: i have seen the tuto which J.Santos mentioned , and afair , there was a trick used to spare the sss-taxes .. .. flipped / reversed normals , i recall . Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 13, 2012 Author Share Posted March 13, 2012 (edited) Hi Erik! Disregard my post if it doesn-t have anything to do but CmiVfx have a lesson that might be worth checking because of the similarity of scenes, approach to shader/render and faking/solving the question of the lamp shade! Good luck! I can't get the method for faking translucency by negating the normal to work in H11 for some reason. Otherwise thats a good method. EDIT: I can't get it to work with PBR to be more precise. Edited March 13, 2012 by Erik_JE Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 13, 2012 Author Share Posted March 13, 2012 IMHO , the flatness and the ' absolutely-white ' lamp needs a bit of tweaking . it is not a source of light in itself so 'i cannot accept' ( so to speak =} ) .. its uniformity and intensity . maybe you can add a pale layer of diffusion on top of it .. also / maybe add some small details ( canvas texture , and some nonuniform-gradient thickness there .. 'where fabric meets the wire' ) p.s.: i have seen the tuto which J.Santos mentioned , and afair , there was a trick used to spare the sss-taxes .. .. flipped / reversed normals , i recall . The shade actually got some nice texture just that it can't be seen because it gets soo damn bright But yes indeed it needs to not shine as the sun. Just need to figure out how to do that. Flipped normal no-go with PBR even if casting color to BSDF. Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 13, 2012 Author Share Posted March 13, 2012 I think the original looks better, dark and dramatic Thanks. Gonna be some action going on with the pens later is the thought so they need to be lit up a little bit more. Quote Link to comment Share on other sites More sharing options...
dyei nightmare Posted March 18, 2012 Share Posted March 18, 2012 (edited) im having this same issue, seems like PBR is not working with the lighting model and the negate normals trick for translucency in H12... Edited March 18, 2012 by dyei nightmare 1 Quote Link to comment Share on other sites More sharing options...
dyei nightmare Posted March 19, 2012 Share Posted March 19, 2012 (edited) Thanks. Gonna be some action going on with the pens later is the thought so they need to be lit up a little bit more. im having this same issue, seems like PBR is not working with the lighting model and the negate normals trick for translucency in H12... btw... are you using the translucency in the mantra surface? there was a little trick where you can add a color ramp, and fake a nice decay in the translucency... ill see if can find it. you can test the translucency with atenuation option in the mantra material anyway. Edited March 19, 2012 by dyei nightmare 1 Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 19, 2012 Author Share Posted March 19, 2012 im having this same issue, seems like PBR is not working with the lighting model and the negate normals trick for translucency in H12... btw... are you using the translucency in the mantra surface? there was a little trick where you can add a color ramp, and fake a nice decay in the translucency... ill see if can find it. you can test the translucency with atenuation option in the mantra material anyway. I haven't found any translucency in the mantra surface so I am just using subsurface scattering atm. Think I am gonna render the lamp shade with MP and just comp it together if I don't find a solution soon. Quote Link to comment Share on other sites More sharing options...
dyei nightmare Posted March 19, 2012 Share Posted March 19, 2012 (edited) I haven't found any translucency in the mantra surface so I am just using subsurface scattering atm. Think I am gonna render the lamp shade with MP and just comp it together if I don't find a solution soon. http://www.sidefx.com/docs/houdini11.0/gallery/shop/vopmaterial/mantrasurface refract tab> Refraction Model > translucency im gonna build a shader Edited March 19, 2012 by dyei nightmare 1 Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 19, 2012 Author Share Posted March 19, 2012 http://www.sidefx.com/docs/houdini11.0/gallery/shop/vopmaterial/mantrasurface refract tab> Refraction Model > translucency im gonna build a shader Totally forgot about that option. This is refractions and subsurface scattering combined. It's slightly better. Quote Link to comment Share on other sites More sharing options...
static Posted March 19, 2012 Share Posted March 19, 2012 total cheat but would light linking work? One for casting on the shade and another for everything else? Or using a really low active radius? Sorry, haven't done much pbr, so excuse my naive response Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 19, 2012 Author Share Posted March 19, 2012 total cheat but would light linking work? One for casting on the shade and another for everything else? Or using a really low active radius? Sorry, haven't done much pbr, so excuse my naive response I have thought in those ways as well. I'll see if i try it later but I am starting to get decently happy with the lamp shade now. It's brighter in the center and some texture can be seen. Added a fill light without shadows to brighten everything up a little. Maybe I should get this thread moved to WIP or something. Quote Link to comment Share on other sites More sharing options...
dyei nightmare Posted March 20, 2012 Share Posted March 20, 2012 (edited) I have thought in those ways as well. I'll see if i try it later but I am starting to get decently happy with the lamp shade now. It's brighter in the center and some texture can be seen. Added a fill light without shadows to brighten everything up a little. Maybe I should get this thread moved to WIP or something. just 3 quick questions, is your lamp light using physical attenuation? if yes, are them giving the soft fallof over the wall or is because any shadow shader?, which are your values in translucency/trans. attenuation? Edited March 20, 2012 by dyei nightmare 1 Quote Link to comment Share on other sites More sharing options...
Erik_JE Posted March 20, 2012 Author Share Posted March 20, 2012 just 3 quick questions, is your lamp light using physical attenuation? if yes, are them giving the soft fallof over the wall or is because any shadow shader?, which are your values in translucency/trans. attenuation? I attached a hipnc with my current settings. It uses physical attenuation through subsurface scattering and refractions. Actually got the best results with cone refractions instead of translucency. No shadow shader involved. lampshade.hipnc Quote Link to comment Share on other sites More sharing options...
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