Hey all, 

 I need a bit of help from the animation experts here.  I am doing another Cg Talk contest and this time part of it is a animation of the scene you create.  
  I did my render of the scene using Ambient occlusion  but when I do the animation there seems to be way more "noise" than when I do an animation with the regular raytracer.  I did render the animation at 480 high and downsizing helps but to render it much bigger will take too much time I think.  I have the GI's  interpolate value  on at 20% which could cause the problem but again turning it off  will drive up render times.  Also will cranking up the photon count help , I am only at 1,000.  
  Any insights on what causes this would be appreciated. 
Thanks
Mike 

Sounds similar to a question answered by Shonner a while back.  If he does not answer this thread it may be worthwhile contacting him.

Hi Mike, Yes, increasing the interpolation and photo count will help. I have better succes with AO when Interpolationis at 50% or better and with photon counts approaching 50,000. BIG DISCLAIMER - This is really contingent on what you have in your scenes. Bump maps can really extend render times with AO. I'll usually try to accomplish "fake" bump maps with specialized highlight and shininess channels when animating to save time. Transparency also will extend times - especially if you enabled "Light through transparency" in the AO settings. If you want to post a frame for trouble shooting I can be more specific with helps. Mark

Mark,

 Here is the final image, the lighting in the animation doesn't look quite as nice but it is okay. I am using "light through transparency"  (but not in the gi settings) for the cloud haze layer and bump on the ground, so a quite a bit of bump in the image.  The image was at 322 X 480 and took 13 minutes to render a frame.  
  I increased the size to 429x640 and the time was 20 minutes for one frame.  My question is which one will most likely decrease the noisy animation. I guess I am not really set up to do animations so that is why I use low settings for the photon count etc., it just takes too long to render.
  Thanks for the input and you have some good info in there.

Very cool Mike. :D You've got a lot of stuff going on there. For animation, usually things with that much depth are actually separate renders later composed in editing. It speeds up renders and allows custom render settings based on content. (it also makes edits less painful) The haze layer and ground bump are the time killers with GI on this. If there is any way you can mod this, then life will be good. For animation, I try to keep render times 3 minutes or less per frame and cheat however I need to to make it happen. ** This is for the attached image above. Model maps are usually rendered with "fake" AO included so you don't have to go the time expense during render. A custom map is usually located in what is the Highlight channel in Carrara with the same map being added or multiplied to the texture channel. The above image is the AO/highligt for some spaceship details. DCG's Anything Goos is also a great tool for this - and it's procedural. For animations, bump is wasted processor usage for anything that is not close to the camera plus it can make things visually muddy during render. People are watching motion not detail. Eliminating the bump on the ground and modifying the texture maps to fake bumps will dramatically decrease render time and make usage of AO faster. --- So - back to cleaning up your render. If changing the maps is not a good use of time right now it's time to experiement. It will be a balancing act between photon count, interpolation and the setting "Improved Edges" for best quality to speed. A combination of reduced photons, increasing the interpolation and enabling the Improved edges will provide the best time-to-quality ratio. There isn't a magic bullet for this problem. :-/ BTW, I recently saw a statistic about who leases the largest blocks of time from the Department of Defense Super Computers - Pixar. :) Animation is the reason render farms were created. Mark

Hey Mark , 

 Thanks for the info.  

  As far as the bump goes , I am using "terrain bump" which really makes  a big difference . If I remove the Terrain Bump function then the terrain looks very flat so I have to keep that for this go around. 
  I could probably do something with the haze layers and the volumetric clouds which also are render hogs.  My problem is I only have Corel Draw,Corel Photopaint and Corel Rave to use as my effects compositing tool.  I did use a layer in the animation for the small lights on the buildings and the main light effect , but this was just a black and white image which I used as a layer and then I used the "Add" as the layer type.  
  I don't know if I can use alpha masks in Corel Rave or photopaint.  Hopefully the haze and cloud layers does the trick.

 Thanks again and that highlight/bump trick sounds cool.

Mike