mental ray render time

[patrick deno desamparado]

buddies, can anyone be my third eye?

i can't seem to know where/what is wrong.
i ran a preview on mr 3dsmax6 which took almost 7 hours.
>is my file too big?
>something wrong with my mr settings?
>or my pc is just slow.

polygon count: 860228
render time is 6:51:04
running on p4 2.4 512ram

tnx

[Juan Carlos Rosalejos]

EEEK!!

Its you settings man.
From what I've learned so far with MR is to never use both GI and FG with equally high amounts of sampling rate.

If you do the math, (taking into consideration your current sampling rate) for every GI Photon sample cast in the scene, it will be refined 2000 times by the Final gather engine. AND if thats not enough to lengthen your render times skyhigh, your radius for GI and Photon is set to .3 which mean, there will be 2000x2000 samples in every .3 radius units in your scene (which explains the splotchiness of the result)

Try to uncheck PREVIEW and check Rebuild.

Start with a modest rate in GI, say 50 then 100 for FG, then work your GI samples.

Good luck

[patrick deno desamparado]

i'll try for the weekend. tnx very much

pls. checkout this tutorial settings...
http://www.evermotion.org/tutorials/...rior/index.htm

[Alex Bicalho]

Start LOW and go UP. Don't start with 2000 FG samples. Nor using FG. With the sampling rate you have in GI you may not even need FG.

Start Low (50 samples) and go up. See the quality increase. And as it increases, keep on going up until you reach the quality you want.

Alexander

[Philip De keersmaecker]

make sure your units AND system units are checked
turn on the 'cm' or meters in your units to see what you're doing
eg.: photon radius = 0,3 ???? 0,3 what??? meters, millimeters,....???
make sure once you got your units worked out ok, that your objects in the scene are drawn in the right scale

if you draw a box around one of your stairs it should add all up : the chair cannot be 5meters-2meters... you'll get the idea right?...

if you don't do all this, it will be impossible to achieve workable rendertimes vs quality... trust me

good luck

[patrick deno desamparado]

tnx. wil post adjusted settings & final render later.

[patrick deno desamparado]

'am not quite done with this.
>problem: why am I having "pixelated" result in final gathering? (see attached)Image was good and rendered fast on gi.
>i tried tweeking almost everything but could not shake it off. I was thinkin something wrong with sampling adjustments(samples/pixel,spatial contrast,etc.) even maybe the fg sample & max/min values, but nothing helps.
>hope someone? help me out on this one.

help is much appreciated

[Frances Gainer Davey]

Hi,

I get that almost every time I use FG and have a manual clipping plane on the current camera.

[patrick deno desamparado]

same here, camera clipped near@3.2m, far@20m

[Alex Bicalho]

By using Fast Lookup you're throwing away the quality. You need to turn it off.

Then you need to adjust the Min/Max Radius so that they generate a good result. A Max radius can't be higher than the size of your bucket. A Min Radius would be around the size of the smaller edge in your rendered view, or around 10% of the Max Radius. There isn't a rule, just guidelines for starting.

Last, start with 100 samples to try the Radius, increase the number of samples as you figure out better quality.

Alexander