View Full Version : Ray Fool

01-24-2004, 07:31 AM
I'm under huge pressure right now deadlines are aproaching fast! The render time is unacceptable. Well it was unreasonable. Until I got out the manual and started tweeking the ray recursion limit. LW's default value of 16 is costly. I haven't paid enough attention to this number. I have an excuse a stupid one but I've got one. The Raytrace extra optimazation check box is located in such a place that I assumed the ray recursion limit had to do with it being checked or not.

Moral of the story it doesen't! check this number always and make it as low as possible.

This first image here is set at AA enhanced medium with ray trace levels at 16. It's about a 15 minute frame on my 933 G4. The hearts image is too big also. it only needs to be a couple hundred pixels high not 1000. If need I'll go down to low AA. It still looks good there to.

wish me luck and do a render dance for me. I'm going to need it today. may the render gods be with us all.


01-24-2004, 07:33 AM
oops I may have posted this one twice.

01-24-2004, 12:17 PM
I rarely ever use more then 3 or 4. Unless you're doing a plate of reflective china in a mirror store, there's usually not that much difference in what I have noticed in past renders on quality between a recursion of 4 and one of 16. But the render times savings can be significant, especially for multiple frame renders.

01-24-2004, 12:43 PM
I've been working on a project like that too. Mine RRL is set at 4 most the time. I had a scene that was rendering at over 17min a frame, and had to change a few things to get the render times down to a reasonable level. I got it down to about 5-6 min a frame. Big improvement. :)

01-24-2004, 12:48 PM
The recursion limit is the maximum number of times a ray can be reflected/refracted, in scenes like this I don't find a reason to have this value higher than 2.

01-24-2004, 12:55 PM
Try a glass bottle with an air layer and HVs inside with raytraced refraction and reflection. You will see a big difference inbetween 2 and 4. I should know.:D