I need Final Gather Help!

[NoshDir85]

I would say that the detailed portion of your image only took up so many pixels, and after it zoomed in more detail at higher resolution=more render time. No way to avoid it other than check your settings and make sure some value isnt cranked crazy high...vague I know!

[PRemmerswaal]

I'm trying out final gather as well this last month and the best way to reduce or improve your render times is by playing with the BSP tree and playing with the sampling level. BSP stands for Binary Space Partitioning. I just had a special lecture with only four people on the subject because nobody was interested (to technicall). But that's a good point to start researching. It's a lot to explain in here, since i just spent 2 hours tring to understand it completely, but I'm gonna be working with it in the next few weeks, so I'll keep you posted if you're interested. Long story short, the BSP tree determines in how many blocks of data MR devides your scene. More blocks with little data is better than big blocks with lot's of data. But small blocks with almost no data are worse than big blocks with a bit of data if you catch my drift. Check it out, and post anything you don't get. The samlping thing was also important. A sampling of -1 to 1 with a very low threshold would be just as good as 0 to 2 with a higher treshhold, but I still have to research this myself. Anyway, If no one esle reply's to you, then these would be my two area's to research. I'd like to get better at it myself so i'll check back! Good luck!

[shantanut]

BSP`s are good. also try and using a spot light which is less expensive than an area light. Also see if you can get soft shadows.

The other way is doing a composite by using a dirtmap.
that way you can control your looks of lights.

lemme know if this helps.

thanks

[retro002]

not sure if this belongs here, but I just read a good article on BSP by bernard lebel, you can find it

here (http://www.bernardlebel.com/wiki/index.php?title=3D:XSI_tutorials:BSP_Explained_To_Artists)

[PRemmerswaal]

@retro002 I'm not sure either, but I'm still checking it out! Looks awesome! But I also agree about the spotlight thing. Also, @junghoonjoe do you mean you are using the HDR as a light source? (I guess so...) Because maybe you can get away with the Physical sky that's new in maya 2008. it's not as great as a HDR, but if it's outside, it'll render a lot faster. (I heard about 4 times faster, but I need to check this out. ) WOuldn't it be an idea to maybe map the color of a spotlight instead of the hdr? Just a thought.

anyway, how's it going? Do you have a Render you can show us? I'm getting Curious here.

[defago]

It would be helpful to know your final gather settings.
If you're using the latest mental ray (3.6, right?), final gather has improved a lot- and you should be able to get away with some pretty low settings (even go as low as 50 rays with a point density of 1). Your min/max scene size can also play a big role in improving fg performance.
Also- remember that final gather doesnt need a precise map like reflections would- blur the hell out of your fg map, and you can keep much lower render settings.

[junghoonjoe]

Thanks for all your help.

For one...my glossy samples where way to high...around 100-150. I was trying to get rid of the noise, which was caused by my not using a filter for the file textures. I also turn on interperation for the reflections and that cut down on the render time.

I was told that the glossy samples should be set around 30-40. What settings do you all use?

I'm using Mental Ray for Maya 2008. I probably should get the full version of Mental Ray...

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