Flickering R & D

Hi recently i did a research on flickering while rendering here are some note that i made during the research.

SSS FLickering

• FG problem
  

• Not 100% sure, but I think it could have something to do with the resolution of the lightmap. Try upping that some (I recall reading or hearing that a low resolution will cause similiar problems. The recommended size was the width being the width of your render and the height being twice that of your render).

Painteffects Flicker

• convert it to poly

• This is most likely a anti-aliasing issue. There is no need to convert to polygons however as
  the maya software rendering options at the bottom in the Paint Effects rendering section there are 2 boxes, Oversample and Oversample Post Filter.

Oversample will improve the anti-aliasing of your paint effects, most likely removing flickering and rendering problems.

Oversample Post Filter will add a further smoothing effect to the paint effects in post.

Of course you take a rendering time increase but this is better than flickering!

More info is available in the mayahelp document section for paint effects rendering options.

Hope this has helped, it fixed my grass problems.

Software Render :

• Is it a nurbs surface? if so make sure you check on 'smooth edge' under Common Tesselation Options
  
  
• adjusting near and far clip planes. bring the 2 values as close together as possible. (high near and low far value
  
  
• depth map shadows, you can fix the problem by increasing the resolution of your dmap shadows.
  
  
• adjusting your filter size, and\or bias size
  
  
• To fix the problem of maya software dmap shadows going through walls at the edge I would make another plane inside the wall.

avoiding flikering without increasing fg rays

• try increasing fgrays density. btw, use the new multiframe fg mode if you're animating with mray3.5.
  
  
• using an AO pass, rather than FG ..then you contorl the blur in post
  
  
• increasing the FG filther value to 1 or 2.
  
  
• increasing point density (point density takes crazy amount of memory.)

Shave and haircut or FUR Flickering

• if You have polysmooth node in DAG chain, get rid of it.
  
  
• If u open ur UV editor window and change ur current frame u will notice ur UV's getting animated. It is b'cos of while smoothing the surface the smooth UV's option would have been on by default. Pls try switching them off and render. it worked for me it may well work for u too. (note- Check the image attached)
  
  
• Render the FUR in seperate pass

Render with GI and Final Gather

• Try using an ambient occlusion shader instead of final gather and then multiplying it over the blinn shader.
  
  
• reduce your contrast even further,0.03. Try Mitchell or gaussian filter. View radius in pixels. Jitter:On. Keep min radius to 1 max to 100 (experiment with this, you can go down to 1,20). Use around 500 rays. Hope that helps.