Hello guys and from me.
I’m new in corona world, but for now i love it.
I’m doing a test scene and it’s a big struggle to get decent noise free image for decent render time.
The image below (2 version - raw and after Ps) are fact of 12h render on 3k res. and still has lot’s of noise. Light rays here are below 800k which is too less.
I try to rid noise at PS but there are not much that do.
Any suggestions?
G.
PS: my workstation is Xeon 1225v2 @3.20Ghz, 32 Gb ram, SSD, Gtx580 3Gb.
PPS: I’ve tried to tweak MSI, Sampling balance and all according to HELP info. here. I’m thinking the problem could be in frosted glass, because when i hide it Light rays go higher around 1,6 mil. rays and after 2 passes drop again to 1,1 and so on… (((
And i found maybe a bug.
After render region when you turn back to View from max frame buffer and when you press Render - corona give you Error creating File output. (I did’t use that option in this file)
After re-open the scene all is working.
Could you try to override the wall material?.. i have a hunch that maybe the texture format in the wall material could be the issue.
I can’t open your scene (dont have max 2015)
Have had this error too, but only when having some render elements activated (i.e. Albedo). Seems like Corona defaults to a none existing file path for render elements, in some some rare occasions.
I tried with deleting all bitmaps on wall and leave it on diffuse colours. Light rays was even lower than previous render.
PS: When i’m doing render regions light rays are much more and stable 1,1 - 1,2 mil.
There is a bug in 3ds max that does this. You need to deactivate render elements or change their path to some existent place. Elements are probably inactive when region-rendering so this pops up when you switch to view. But I’m not completely sure about this so I’ll check it and also the scene.
There are some things that are causing exceptional noise in this scene:
-reflective caustics - ligths (especially IES lights which may be problematic) facing reflective walls which have wrong materials (example: reflection fresnel ior at 20 or more)
-wrong materials - apart from very reflective walls, also the glass door have too high reflective ior and they had some color in diffuse slot, this is wrong - when creating glass use diffuse level 0 or pure black color, if you want the glass colored either use refraction color or absorption
The scene renders ok-ish when using grey override material so I’m 90% sure slow rendering is because of materials.
Was this scene converted from some other renderer?
Hello maru,
yes the scene was converted from vray 3.1 scene, that we work in our studio. I just get that scene and used corona converter to test some things. I will check all things that you mention.
Thank you.
I will write later.
“Freshly” converted scenes usually need some manual tweaking. Try to make everything as “physically correct” as possible - use correct reflectivity, fresnel values, glossiness, brightness.
So generally after maru’s comment i edited almost all materials (ior and albedo)and light rays jump up from 0,8k to 1,6-1,8 mil.? Also i removed all lights with ies and scene was lit only with corona light as spheres.
I will try to improve more - to go above 2 mil.
So here are an update of my process.
I re-edited scene and rays goes up to 2,5 mil.
I had a problem also with corona DR - all my slaves didn’t want do render anything. I read almost every forum threads here and nfo files - finally slaves still giving me these ping errors but all they DO rendering job!
