sebkaine Posted March 6, 2015 Author Share Posted March 6, 2015 (edited) I think the secret is like in any modern path tracer where you have to become a noise hunter and master exactly how noise is added at each pixel. so i use the traditional technics where you outpout - direct diffuse AOV - indirect diffuse AOV - direct reflection AOV - indirect reflection AOV - Pixel Sampling AOV For each layer you control the amount of noise it create and you try to play with the pixel sample to get the minimum good enough pattern this is an interesting read http://www.cggallery.com/tutorials/vray_optimization/ https://support.solidangle.com/display/mayatut/Removing+Noise Edited March 6, 2015 by sebkaine Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 6, 2015 Share Posted March 6, 2015 As we now are heading out on noise hunting safaris we should also keep an eye on the another noise reduction technique; Pixel Filtering - Ray Histogram Fusion was added in H14, so far tests have shown it to be quite blotchy but that is probably just the operator You can now write your pixel filter too: 'Can now write custom pixel filters for Mantra' http://www.sidefx.com/docs/hdk14.0/_h_d_k__changes_14_0.html#HDKC14_0_vray_pixelfilter Quote Link to comment Share on other sites More sharing options...
sebkaine Posted March 6, 2015 Author Share Posted March 6, 2015 (edited) Marty if you plan to go to a noise safari, i would also advise you to buy a rocket luncher : http://www.neatvideo.com/ Edited March 6, 2015 by sebkaine Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 6, 2015 Share Posted March 6, 2015 (edited) I think Neat has a 10 or 11k pixel limit - which is a pixel sample of ~5 at 1920x1080 The file sizes are when sub-pixeled, and AOV'd, are atrociously huge then too; in-render pixel samples have to happen at some point. Edited March 6, 2015 by tar Quote Link to comment Share on other sites More sharing options...
eetu Posted March 6, 2015 Share Posted March 6, 2015 (edited) Pixel Filtering - Ray Histogram Fusion was added in H14, so far tests have shown it to be quite blotchy but that is probably just the operator You can now write your pixel filter too: Ah yeah, almost forgot! This is probably the perfect example scene for RHF to shine It is indeed a bit blotchy, and can eat away high frequency detail (see e.g. the stairs here), but all in all it really eats the noise for breakfast. I changed the material to clay and pixel filter to the default RHF, otherwise it's all the same. Render time 26min for 1080p. Edited March 6, 2015 by eetu 1 Quote Link to comment Share on other sites More sharing options...
eetu Posted March 7, 2015 Share Posted March 7, 2015 (edited) Refined a bit; from what I remember about RHF I decided to feed it more but lower quality pixel samples, and I also lowered the threshold a tad (20->18). If you look at details, the result is noticeably better, less blotchy, more details but more noise. I still would bet that this does not hold for animation though, and just having more involved materials/textures would surely hurt. 29min for 1080p Edited March 7, 2015 by eetu Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 7, 2015 Share Posted March 7, 2015 Ray Histogram Fusion is a win for volumes like smoke. Smooth, lacking detail and noisy are well suited to it! set it to ~ 'combine -t 10' Quote Link to comment Share on other sites More sharing options...
Mzigaib Posted March 7, 2015 Share Posted March 7, 2015 Awesome guys!It is really good to know about this filter option. Quote Link to comment Share on other sites More sharing options...
Netvudu Posted March 7, 2015 Share Posted March 7, 2015 I´m joining the ranks of the people who think that VRay example is only valid for stills. I admit you can play with all the values to have nonflickering renders, but it will certainly either a) increase substantially render times, or b ) lower the overall quality. You cannot compare that solution with a PBR brute forced one. It´s not on the same league. And yes, Mantra is pretty awesome but you gotta do your homework. Thanks a lot for the sample scene, Emmanuel. Quote Link to comment Share on other sites More sharing options...
sebkaine Posted March 7, 2015 Author Share Posted March 7, 2015 (edited) You are right Javier i will ask to him to make a small animation to see if it flick. Well i am now on par with redshift , because after optimising the direct sample / indirect sample i now have 1080P => 18 min i have also try to make my own shader but it wasn't faster than the mantra one ... apart from finding a way to optimise at shader level, i think we have push the stuff close to the max. I have also try the RHF filter , but i find that it do an operation close to lightroom denoiser or neat image denoiser, it destroy the information at some place so i find after testing that the best one is Blackman it is exactly beetween Catmull and Gauss. not too sharp / not too soft ... i prefer to apply the denoise destructive operation in post well i will try next week to send an animation when i will have some time ... as a side note i find that houdini have a tool to convert .i3d to brickmap so this mean that like prman houdini has ptc and bkm equivalent. http://www.sidefx.com/docs/houdini14.0/nodes/out/brickmap http://www.sidefx.com/docs/houdini14.0/nodes/vop/pcwrite I would be curious to know why they are not use for baking ? Edited March 7, 2015 by sebkaine Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 7, 2015 Share Posted March 7, 2015 I'm noticing excellent startup times in Vray for Maya and Arnold for Houdini - a few seconds - whereas Mantra is currently taking many more seconds - are you all getting the same on Windows /Linux? I'm thinking it's an OsX 'feature' Quote Link to comment Share on other sites More sharing options...
Mzigaib Posted March 7, 2015 Share Posted March 7, 2015 Can you tell how many seconds? I don't have Vray or Arnold here to test. Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 8, 2015 Share Posted March 8, 2015 Mantra was taking ~30sec to get going, Arnold ~4sec, Vray ~ 4sec Quote Link to comment Share on other sites More sharing options...
sebkaine Posted March 8, 2015 Author Share Posted March 8, 2015 On windows 7 the rendering start after 10 seconds Quote Link to comment Share on other sites More sharing options...
eetu Posted March 8, 2015 Share Posted March 8, 2015 I have also try the RHF filter , but i find that it do an operation close to lightroom denoiser or neat image denoiser, it destroy the information at some place so i find after testing that the best one is Blackman it is exactly beetween Catmull and Gauss. not too sharp / not too soft ... i prefer to apply the denoise destructive operation in post Yeah, it's a bit of a cheat, but I'm hoping that there is a genuine use case for it. Marty's tip about using it for volumes was very good info! It should be able to be better than the post denoisers as it uses the info of all the individual smaples and not just the filtered end result. (On the other hand, things like neatvideo have the advantage of using previous and future frame info as well) I rendered a short 50 frame camera move - it looks quite good at first look, but when you look closer it does have some of that flickering blotchiness. 22Mb .mov, 390Mb png sequence. Should try this with some actual materials.. BTW, the 18 minute render looks great! 1 Quote Link to comment Share on other sites More sharing options...
Mzigaib Posted March 8, 2015 Share Posted March 8, 2015 (edited) Awesome! I could totally use this on production and yeah using the sample filter is better than use post filters an image filter would mess with the details in the entire image like the internal thickness of the individual windows. Edited March 8, 2015 by Mzigaib Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 8, 2015 Share Posted March 8, 2015 (edited) Redshift Gtx980. 24min - 1920x1080 Primary GI Engine: Brute Force Seconday GI Engine: Irradiance Point Cloud Brute Force GI: num Rays 2531 Unified Sampling: min 64 / Max 389 *warning 40min experienced operator * Full res tiff: https://www.dropbox.com/s/vrvtk8to6eythf4/RedShift24min.tif?dl=0 Edited March 8, 2015 by tar Quote Link to comment Share on other sites More sharing options...
sebkaine Posted March 8, 2015 Author Share Posted March 8, 2015 (edited) @eetu => have you check the lock point sampling option in the mantra ROP ? @marty => Redshift looks really cool ! i'm quite sure we can go less than 10 minutes with some practice and a good GPU. i only have a GF660 to test ... Edited March 8, 2015 by sebkaine Quote Link to comment Share on other sites More sharing options...
Guest tar Posted March 8, 2015 Share Posted March 8, 2015 Redshift looks very cool- at a guess perhaps 2-3 years away from making it into Houdini. As I currently don't have too much time to spend in Windows what are some good settings to use in Redshift? Quote Link to comment Share on other sites More sharing options...
sebkaine Posted March 8, 2015 Author Share Posted March 8, 2015 i have only play with it for less than an hour but Irradiance Cache / Irradiance point cloud should be a good start ! Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.