thick Black line due to motion blur when rendering

[phix314]

Need a picture.

[UGG]

http://forums.cgsociety.org/attachment.php?attachmentid=146940&stc=1

black lines in top left & right corners of the walls, dont think this is due to lighting but motion blur in render settings?

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this is shot without motion blur, after preview render

http://forums.cgsociety.org/attachment.php?attachmentid=146941&stc=1

[kanooshka]

It's really hard for me to say, I have no experience with motion blur myself. But I have a couple possible theories. First of all, I think this could be an alpha channel issue, just because I'm seeing a white line on the edges of the black bar, try disabling alpha channel for the render and see what happens. If not that, do the black lines match up with your geometry, are there edges where the black lines start and end? If so try flipping the normal of that plane. Finally, between the two images posted, did you only change the motion blur setting or did you use a preset? Which renderer are you using anyway?

[UGG]

thank u very much for the help, under the render settings, i already have the camera alpha mask channel turned off & I have changed under motion blur smooth, from alpha to color, the problem is still there.
when u say, (do the black lines match up with your geometry, are there edges where the black lines start and end?), on the left hand side of my wall, it meets with the roof & where the doors are, the wall has holes for the frames & doors, the right hand side is a duplicate of the left, also at the end of the hall there are no walls, with a spotlight pointing down the hall from different ends, so why are the black bars different on the left & right hand side of the walls?, am i on the right trail of thought? from what i understand which isnt much, i have read that u can have light gap errors, thin bright lines, often appear from the intersection of two surfaces, casts a default depth mapshadow. a light gap appears along the intersection seam. But i have turned off each light individually & the line is still there, lol only when i turn off the motion blur in the render does it go away.
Currently iam using the software renderer & using a book learning maya 6 foundation & it says to turn on motion blur & set motion blur type to 2d.
i quite like the effect & would like to use this setting but if worst comes to worst i supose i can go with out, i have never fully rendered anything in maya before, lol
I will try flipping the normals
really apreciate the help ta :)

[kanooshka]

could you post a wireframe screenshot please?

[UGG]

i have flipped the normals & yes the roof & left walls where facing outwards, now they are all facing in, it changed the 1 wall but now they both have thin triangels going down either side?

http://forums.cgsociety.org/attachment.php?attachmentid=146995&stc=1

[UGG]

wire frame with normals http://forums.cgsociety.org/attachment.php?attachmentid=146996&stc=1

[UGG]

wire frame with lights from sidehttp://forums.cgsociety.org/attachment.php?attachmentid=147001&stc=1

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