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pilkiwilky
01-15-2011, 10:14 AM
I have an object I am animating going from opaque to half transparent in the middle of the scene.

When the object I'd opaque, render speeds are super... The second I start the transition from 100percent opaque to slightly transparent, my computer grinds to a snails pace... I have 30 of these animations to render, so anything anyone can offer would be great.

I use classic camera at AA high level

Would the advanced camera be faster? I've never used it.

Thanks

Lightwolf
01-15-2011, 10:22 AM
I have an object I am animating going from opaque to half transparent in the middle of the scene.

When the object I'd opaque, render speeds are super... The second I start the transition from 100percent opaque to slightly transparent, my computer grinds to a snails pace... I have 30 of these animations to render, so anything anyone can offer would be great.

Render twice... once with and once without - then fade in a compositing package.

Cheers,
Mike

Matt
01-15-2011, 11:44 AM
Also, do you have _any_ diffuse on? That can slow down transparent surfaces quite a lot, which is not unique to LightWave, other apps have this too, something to do with rays, Mike will be able to tell you the theory!

:)

archijam
01-15-2011, 04:08 PM
I agree with mike, sounds like you (potentially, don't know the scene) just need two frames, one with and one without, and fade them together in post.

..

I have wondered in the past if there would be some kind of trick with using a black+white (not greyscale) noise pattern at a tiny scale in the clip map channel.

Obviously also some AA will be essential. Plus animating would be trickier (probably have to play with scale or mix), since clipping is always on or off.

Is there a way to get clip maps to fake a semi transparent effect?

Hieron
01-15-2011, 04:29 PM
Like Mike said. Dissolving objects with GI gives alot of issues too, same thing for such cases. If possible ofcourse.

dwburman
01-15-2011, 05:28 PM
Are you animating the dissolve setting in the object properties or the transparency channel in the surface settings?

01-15-2011, 05:51 PM
Render twice... once with and once without - then fade in a compositing package.

Cheers,
Mike

Sorry if I abuse of this thread, but Lightwolf can you give me a help with the problem I posted in this thread http://www.newtek.com/forums/showthread.php?p=1100704 please? I have extrader and shadermeister if it helps..
I often work with transparent objects so further explanations are welcome :D

JonW
01-15-2011, 09:43 PM
Transparent & reflective surfaces will hurt render times, & if they are a large % of the render area, render times will be really painful.

Reduce the complexity of the transparent object. The least number of transparent surfaces that line up, the better.

Try lowering Ray Recursion Limit to 1 higher than the number of transparent surfaces you have. If 1 too low you will see the background.

Perspective camera can be quicker.

akademus
01-15-2011, 11:29 PM
Hi Joe,

Shadows (soft raytraced, like from area or linear lights) tend to make renders much longer when calculated through transparent models.

It really depends from your scene...