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blacknoise
08-20-2004, 12:23 PM
hi there!
im working on a serie of a short animations and some strange errors occur while rendering the paint effects in maya software. see the attached image.
note the sharp edges around the area that is out of focus. how can i get rid of them? render settings are set for the highest production quality.

i would really appreciate any info on this problem because of the short deadline i just have to reach.

thanks,
blacknoise.

chocobo2k
08-20-2004, 02:18 PM
from my point of view, those artifacts you pointed to are just the paintFx strokes which are in focus of the camera and thats why they appear so sharp because there is no tranistion between the nearest and farthest stroke and thats why you see them as artifact.

blacknoise
08-20-2004, 02:46 PM
yes... but why there is no transition??? from my point of view there should be some... :\ bummer...

do you think that exporting z-buffer and applying dof in post production should do this job better?

chocobo2k
08-20-2004, 04:19 PM
As far as I know, Maya DOF is fake it just do 2d blur on the area out of focus just to mimic DOF so it appears so bad and unreal in some situations just like you have. So you can either use MentalRay as a renderer and attach DOF lens shader to your mentlaray camera lens shader after converting your PaintFx strokes to ploy. or just render the z-buffer as you mentioned above and do it post productions.

danylyon
08-20-2004, 06:19 PM
To my knowledge, Paint Effects is a post effect, that gets applied AFTER the image has already been rendered. It uses the Z Depth Channel to determine where the paint effects are hidden etc. That means, Paint Effects, aren't in the Z Depth Channel. Unfortunatly, Maya's DOF uses the Z Channel to blur the image. So yeah, it will never work well (well Maya's DOF never work's well to begin with ;)

So you'll have to "construct" you're own Z Channel with shaders. There's one at highend 3D, If I'm not mistaken (never tried it though), you should be able to assign it to the paint effects aswell. Then you've got a nice Z Channel, with paint effects, and you can use something like www.frischluft.com (http://www.frischluft.com) to make a DOF.

Or convert them to Polys.

blacknoise
08-20-2004, 08:07 PM
thanks for your answers... even if they did not make my day better ;)))

best regards,
black noise.

Duncan
08-20-2004, 08:56 PM
Try bringing in the far clip. It could be that the blurring for the far boundary background pixels is maxing out the blur( I think this can also slow the blur phase ). Also play with the various depth of field settings. It looks like your focal range is really shallow, so that everything even a little outside this range maxes out the blur. There should be a gradual transition in the Maya depth of field as long as the settings are good. However depending on what you are blurring there may be artifacts with blurry forground elements.

Duncan

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