strange artifacts when rendering with FG

# 1 07-08-2005 , 12:00 PM

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Hello

I'm getting this strange jaggies or whatever it is , when i render with FG including a incandesence Light dome.

I'm used 1000 rays , min AA 1
Max AA 3

filter , mitchell

user added image

i need a solution i can't get it to work.

tck

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# 2 07-08-2005 , 10:10 PM

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After you render out, Click on the 1:1 button.

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# 3 08-08-2005 , 10:07 AM

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output any format is always 1:1

tck

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# 4 08-08-2005 , 11:19 AM

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Correct, but it may not be displayed as 1:1

If the window it opens the render in is smaller than what would allow 1:1 display of the image, maya will render it to scale but shrink it to fit the window.

The 1:1 button isn't there for looks user added image

Well that's my 2 cents worth.

Cheers
Paul

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# 5 08-08-2005 , 11:29 AM

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Is there any possibilty to save a output file for example , jpeg or tiff beneath 1:1 ?

But back to the point.
My FG rays aren't reaching those points , where these artifacts occure...how can i fix this.

tck

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# 6 08-08-2005 , 11:34 AM

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changing camera angle can help to get rid of these unlit areas.

increasing u\re irriadiance dome may help too , correct me if i'm wrong?

tck

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# 7 08-08-2005 , 11:35 AM

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Right click on the image and select Save File, then select the format. I wouldn't recommend jpg, because maya seems to output a crappy image. Try TGA or something. In anycase you will see the file formats available when you go to save.

Cheers
Paul

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# 8 08-08-2005 , 03:10 PM

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I have problems figuring out how to lit these lil tiny area's with my final gather rays.
As u can see , these tiny spots don't get lit with my FG rays (i used 1000 rays including a lightdome to bounce off these rays).
I'm searching for a solution to lit these lil area's.

I'm not asking how to save a output file with or without image compression to preserve the image quality.

The jaggies (unlit area's) have nothing to do with image compression.

tck

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# 9 12-08-2005 , 05:40 AM

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Its been a while since I've messed with final gather settings but thats where you wanna look. Min and Max radius under the final gather menu I believe are your ticket. The values you put in are totally dependant on scene scale. If I remember correctly you should set max to 1/10 of your scene size and min to 1/10 of max ... something like that ... I'd have to read up on it again. You could also just try significantly increasing the number of rays.

cool model

Dave

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# 10 26-08-2005 , 08:15 AM

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I ran into a similar problem -
How big is your scene? Mental Ray actually appears to have a default render clipping plane (Haven't tried to mess with mine yet). I think its a bit over 1000 units.

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# 11 06-09-2005 , 03:51 PM

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I am having exactly the same problem on a plane I am doing. I'll post some images later tonight. Did you scale the model up when you worked on it? I think it is related to that. I did do FG on another plane and did not have any problems. The only difference between the two is that this one was scaled up early on significantly. I did try different settings for the Min and Max but that didn't fix it.

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# 12 07-09-2005 , 02:01 AM

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Well, I played a bit with it just now and it definitely had to do with the scaling of the objects. I adjusted the min and max radius to much bigger values than I thought, and here are the results, judge for yourself. FG rays are only 200 on both pics, the max radius is 1500 and the min is 200. That was the best combination I found. Raising FG to 500 did not make it better. Also, the sampling quality filter was set to triangle. Everything is default. I did the testing on the same project I was working on that gave me problems. I am sure that if I had started a brand new project with normal size models max/min radius of zero would have worked (which it has for me before).

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# 13 23-09-2005 , 01:01 AM

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herr_klaus

Just curious.....did you reverse normals on your dome?

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# 14 23-09-2005 , 08:59 AM

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I dont think you solved the problem as you've lost all the detail around your sphere (which is probably cause by such high values in the min and max distance). So it may look like it's solving the problem but I dont think it actually has.

I'm not MR expert but min and max radi that high will not give good results unless your scene scale is huge.

Post the scene file up if you want and we can look at it.

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