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hot pixel problem :(

Posted: Mon Jan 16, 2012 11:50 am
by danyz
Hello. I'm working on 3ds max 2011 and when renderig the visible hot pixels. Despite setting a high sampling rate to 16,000 are still clearly visible white dots. What I am doing wrong? are there any special settings to luminous objects? I do not want to use the option of removing these pixels because it softens the image.

I apologize for my language, I'm using Google Translate.

Re: hot pixel problem :(

Posted: Mon Jan 16, 2012 9:52 pm
by roeland
Fireflies are a normal occurrence in scenes like yours, they appear when there are a lot of shiny objects in the scene.

You can use the PMC kernel instead of the path tracing kernel. It generally converges a bit slower but is suffers much less from fireflies. You can also increase the roughness of some objects in the scene.

If you need a clean render faster, you can use the direct lighting kernel with diffuse-only indirect light. This will however not render any caustics.

--
Roeland

Re: hot pixel problem :(

Posted: Wed Jan 18, 2012 5:21 pm
by danyz
hotpixel also occurs in simple scenes: (

teapot test.zip - 3dsmax2011 file

Re: hot pixel problem :(

Posted: Wed Jan 18, 2012 5:53 pm
by face
I don´t know many about Max, but normal the unit you choose is all the same.
A vertex at 1,1,1 can be mm, cm or m and is ever located on 1,1,1.
I think you will see it if you export it as obj.
When the unit is different, the position should be different in the file.

Try to scale the scene down by factor 100.
Maybe i´m wrong and the plugin scaled the scene internal...

face

Re: hot pixel problem :(

Posted: Wed Jan 18, 2012 7:32 pm
by Karba
danyz wrote:hotpixel also occurs in simple scenes: (

teapot test.zip - 3dsmax2011 file

Have you received your scene with my editing?
You have to be careful with light source form and remove poligions which do nothing like light inside a wall.

Re: hot pixel problem :(

Posted: Wed Jan 18, 2012 9:04 pm
by danyz
hi

Tomorrow morning i'll try remove poligions inside a wall. I did not think that this can be a problem.

Thank's:)

Re: hot pixel problem :(

Posted: Wed Jan 18, 2012 11:23 pm
by t_3
danyz wrote:I did not think that this can be a problem.Thank's:)
explanation: if you place an emitter (partly) inside a closed surface like a wall, it'll still emit light _inside_ the wall, and thus octane needs a lot more time to calculate the image to a certain noise level - even if you won't ever see that inside light. remember that meshes are not solid but just surfaces...

Re: hot pixel problem :(

Posted: Thu Jan 19, 2012 1:45 pm
by danyz
Thank you very much! This was precisely the cause of the problem. Now everything looks very good.