black dots and dirt in corners of sliding windows

[ralphboudiwan]

hey guys, this thing is getting on my nerves. how can i get rid of black dots and dirt in the corners of sliding windows and doors? is it because no enough light is getting there?? can someone help?? see if you render with scanline using skylight nothing of this sort happens but when you do it with vray you get the dirt and black dots!!

[Chris MacDonald]

Post a picture.

[ralphboudiwan]

[ralphboudiwan]

just look at the corners of the sliding doors some black lines and dirt appear!!thank u in advance for your attention

[abhaysingh]

Hi Ralph,

I think overlapping of polygons( door frame & wall) causing the black & white faces.Also, if you see, the problem is only visible in similar

door object/mesh & nowhere else in the scene.So, check for overlapping.

[Chris MacDonald]

Agreed. It looks like a problem with the geometry/modelling, almost like there is a gap of an inch or something between the floors.

[ralphboudiwan]

hey guys, thks for your replies! really appreciate it but the problem seems to linger. it is not a problem of geometry.any more suggestions?? it seems not enough light is getting to some areas of the windows especially the floor of the door.

[abhaysingh]

Hi Ralph,

Can you save select geometry of wall-doors & share the max file ??

[ralphboudiwan]

sorry dear singh

but there is a problem in uploading the max file

but the problem is with a simple slidingwindow rendered with default v ray settings and u get the problem

Edited June 10, 2013 by ralphboudiwan

[abhaysingh]

I think it is a clear case of overlapping.Can you delete one of those polygon(especially the bottom one) & check if there is another polygon behind it?? Sorry for pushing you but it doesn't seems to be lighting problem.

[ralphboudiwan]

dear abhay,

look at the above sliding window in my lat reply. this is a very simple slidingwindow with default settings and the problem is clear.while if u render it with scnline. the problem disappears.

[abhaysingh]

Scanline will render just fine even if surfaces are overlapped.Anyways, I found a similar thread on cgtalk but unresolved & closed.Could you increase the "secondary ray bias" in global switches to 0.01 in vray settings & render again to check if it solves your problem.

By the way here is the thread http://forums.cgsociety.org/showthread.php?f=6&t=1033386&page=2&pp=15

[ralphboudiwan]

dear abhay,

didnt seem to work

[Nic H]

thats double faces

where is this geometry coming from?

[ralphboudiwan]

hey ninic,

this is a simple sliding window.

[ralphboudiwan]

hey ninic, what do you mean by double faces??

hey singh, the link that you gave me worked well yesterday. the idea of close to origen thing.today, didnt work.thk you aw for your help.

[Nic H]

double faces is where 2 or more polygons are overlapping in the same space. it shows up in vray as nasty black blotchy areas.

its too black to be poor GI

 

did the 'simple sliding door' come from some weird software or AEC object perhaps?

Remodel it from scratch I i 99% think that problem will be gone!

[ralphboudiwan]

hey ninic, no it came from AEC extended as i recall. i will try to do what you said. thks for the help sir.

[abhaysingh]

I've just made sliding window through "create\geometry\windows".I never tested it before but geometry came out so bad.Don't use it.Make your own.As I told you before, its a clear case of overlapped faces & in this sliding window which I've just made, there were 3 polygons sitting over each other.

Edited June 11, 2013 by abhaysingh

[Rich O]

Check your normals. But yes, would more than likely appear to be double faces or some other dirty geometry.

[Nic H]

has anyone tried reading this thread using a potato?