AA - Flicker

[sandy_maith]

Thanks Remydrh
what sampling values does is clear but how actually quality works? does it like sort of correct the problem areas where more sampling is needed. Does it affect shading as in fast rasterizer. ..
Do i need to increase my samples first and then quality or is it like to keep samples to some fixed values (like 4/64) and just keep increasing the quality value till you get the desired quality!
Which of these will consume more RAM?
How to use cutoff value? What happens when we dont lock quality and cutoff?
There are many questions right now.

[Remydrh]

You can take a look here for more explanation: http://elementalray.wordpress.com/20...or-the-artist/

[sandy_maith]

perfect...thanks

[sandy_maith]

OK...there are few tests i did with this file..
https://www.dropbox.com/s/obv84mhs5d...t03_merged.zip
1. Increasing quality to remove sampling artifacts dosent help much but increasing samples does...i've tried values like 100 on quality but the flicker was still there. This goes little against the article mentioned above.

2. My frame render times were ranging from 58 minutes to 2 hrs per frame..whenever i stopped the render and resumed it, my render time increased like crazy..is it a memory flushing issue?

3. To get a decent quality without flicker, the render time was still way lesser with unified approach than normal AA sampling.

You are free to test the scene and lets see if we can get a better approach to get a good render in less time

[Remydrh]

If your Quality parameter is already forcing your samples to a high value then yes, you would have to increase your samples max.

Usually I keep my samples very wide, maybe min 1, max 500+ and then use Quality for everything. With my ceiling so high I might never reach it.

Remember if you really increase your Quality (2+) that you can introduce a small amount of Error Cutoff. Usually 0.01 for each step in Quality. So Quality 4. would be 0.04. I don't generally go above 0.06 for Error Cutoff.

With mental ray 3.10 I find I can reduce my Quality for complex scenes where my range is about 2-6 where before it might be 4-10.

[sandy_maith]

If your Quality parameter is already forcing your samples to a high value then yes, you would have to increase your samples max.

Usually I keep my samples very wide, maybe min 1, max 500+ and then use Quality for everything. With my ceiling so high I might never reach it.

Remember if you really increase your Quality (2+) that you can introduce a small amount of Error Cutoff. Usually 0.01 for each step in Quality. So Quality 4. would be 0.04. I don't generally go above 0.06 for Error Cutoff.

With mental ray 3.10 I find I can reduce my Quality for complex scenes where my range is about 2-6 where before it might be 4-10.

Thanks for the info Remydrh
After all permutaions and combinations the best (flicker free) i could get on this scene is 57 minutes at 1080 HD.
Will it be possible for you to have a look at the scene foliage is the most daunting task to render without flicker.

cheers

[Remydrh]

I'm not sure if your flickering is based on anti-aliasing or lighting. Do you have an example somewhere?