heavy glass environment

[chuzzlewit]

Apart from cutting down the ray recusion limit is there any way to get faster renders in an environment heavy in glass - the image size, number of lights and objects must stay the same but the rest is up for grabs.

[Gui Lo]

YOu can try the speed up trick that is being talked about.

Basically: Put a plane of 100% Transparency in front of the camera. That's it. You can devide it into smaller sqaures. Oh, yes, make sure the normals face the camera.

This forces LW to render only what is seen by the camera. For instance this stops it from rendering part of an object that will be hidden by another object.

Caution: Can lead to longer rendering times so best to render a single pass first to test. Also stops Shading Noise Reduction from taking effect.

Hope this helps

Gui Lo

[chuzzlewit]

Not quite sure what you mean. Do you literally place a transparent plane in front of the camera - (this is for an animation) and if so why would that force LW to render only the seen objects. Could you Illuminate me further.

[trentonia]

You could try to experiment with turning off the render transparency, render refraction, render reflection functions in the render options dialog box. Turning these off will definitely cut down render times and different combinations may still give you what you want. Other than that, you can turn every option on and still speed up render times by going to http://www.respower.com

[chuzzlewit]

A fan of Respower - however limited rendering at the moment - the queues have been bad for a couple of days there - someone he making star wars 5. The idea as well was to cut down on the time at Res. Don't suppose it makes any difference if you cut down the reflectivity say from 20 to 5 percent?? I may turn all reflection off altogether although I fear this may make it look bland.

[Gui Lo]

Sorry for the confusion.

Please take a look here:
http://www.funnyfarm.tv/thelab/rendertrick.htm

Another thing may be to reduce the 'Ray Recursion Limit' setting in Rendering Options. I think a setting of 7 is just about OK.

Gui Lo

[earlye]

Originally posted by chuzzlewit
A fan of Respower - however limited rendering at the moment - the queues have been bad for a couple of days there - someone he making star wars 5.

Thanks for being a fan! We truly appreciate it! As for the bad queue, we've got some exciting news. Here it is, straight from the horse's mouth...

ResPower's farm now utilizes time-slicing. When a computer decides what task to start on next, it will ignore the current user if that user has had the computer for "n" minutes. ("n" is currently 30, but we reserve the right to tweak that value as necessary). This means that even if the queue is "bad" you will get significant speedup over a single machine, and your frames should never sit in the queue for an exceedingly long amount of time.

Note that the farm slices time on a per-user basis, not a per-job basis, so splitting your job into a bunch of little jobs will not get you more farm time than other users.

As always, you can also get significant discounts (up to 50%) by purchasing your hours in advance on the Manage Account page.

[chuzzlewit]

Very interesting link and when you think about it it makes such simple sense. I'm really keen to try it. I will report back how it affects the glass heavy environment so we may all be the wiser. Thanks Earlye - I will be sending you some stuff shortly. Discount eh...

[lone]

i just did a render with what amounts to a double-paned window - after twenty minutes, it still hadn't rendered a tenth of the surface (this was in a large scene, and the glass itself was way away from the camera). got sick of waiting, and turned the reflections off on the inside surfaces only - now the scene renders in like five minutes. if you are not doing close-up work, try this.