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Wilfrick
11-13-2012, 10:30 AM
Hi,

I have a problem: in the scene 1 object must be "unaffected" by DoF (all the obj in the scene must have dof applyed, but one of them no).

I can't make 2 separate render (one for the scene with Dof and one for the obj without dof) because the obj flys inside a HV sprite particles with a lot of glow and a a lot of surfaces are reflective ("all" reflect "all")... so the render must be one... all together.

In past I tried to export a depth buffer and compose the sequence in AE, but the result was not very good.
The LF-stop doesn't resolve: some parts of the object are blurred, only the center is very "clear".

There is a solution to exclude a single object from dof?

thankyou
Bye

jwiede
11-13-2012, 10:40 AM
When in doubt, cheat: Is there any way you can expand the depth for everything else (scale up, perhaps) such that the non-DOF object falls entirely within the new focal range?

Wilfrick
11-13-2012, 11:00 AM
When in doubt, cheat: Is there any way you can expand the depth for everything else (scale up, perhaps) such that the non-DOF object falls entirely within the new focal range?

:(
I tried this way, but I lost (or modified) a lot of reflections... so now I set the scale of the scene to have a "decent" compromise between size and good reflection.
However this is the "less bad" solution... and I think that if can't find something other I will must increase more and more the size of the scene (like you write: expand everything else so the no-dof obj fall in the focal range... and maybe move the camera more near to the obj and decrease the lens focal lenght if the image isn't too much "distorted").

DrStrik9
11-13-2012, 12:40 PM
Render twice: once without DOF, and once with, then compose?

Wilfrick
11-13-2012, 01:26 PM
Render twice: once without DOF, and once with, then compose?

the obj flys in a "cloud" of particle (HV sprite) that simulates a cloud of gas. Very difficult to compose 2 sequences with alpha and trasparent HV particles... the result isn't good (or maybe I'm not "good" to compose semi-transparent objects.... transparent on transparent, problem with alpha). So I need to make only 1 render.

toby
11-13-2012, 01:47 PM
You should still be able to render those separately, for the first pass, set your non-dof object to unseen by camera but allow it to reflect in the scene, then do the opposite for the second pass, and it sounds like you need to matte the HV. Glows are best done in post too; it's a 2d post-process in lightwave anyway.

This is a great example of how & why knowing how to composite is so important / powerful! I don't know of any renderers that change the dof per-object.

toby
11-13-2012, 01:51 PM
the obj flys in a "cloud" of particle (HV sprite) that simulates a cloud of gas. Very difficult to compose 2 sequences with alpha and trasparent HV particles... the result isn't good (or maybe I'm not "good" to compose semi-transparent objects.... transparent on transparent, problem with alpha). So I need to make only 1 render.
It should be do-able in some way or another. One method is to set the matte flag on all geometry to black, then render the HV pass.

I've been doing dof with HV recently too, and this has worked great, and in my case, sped up renders a great deal.

Wilfrick
11-14-2012, 07:07 AM
It should be do-able in some way or another. One method is to set the matte flag on all geometry to black, then render the HV pass.

I've been doing dof with HV recently too, and this has worked great, and in my case, sped up renders a great deal.

Following your way I have a good result, compositing inside AE:

Layer 1: all the scene with DoF (unseen by camera for The obj and no HV -speed up the render!!!-)
Layer 2: only The obj without DoF (no HV, unseen by camera for all other)
Layer 3 additive: only HV (without DoF.. no need on HV) and all other with matte flag black (no reflections really speed up render).

The look is really near of LW render, ofcourse there aren't the reflections of HV on objects, but it is a little "gap" and I'm sure that the customer will not see.

Ok, this is a good result. Thankyou!!! without your help I never think about matte objects inside HV.

toby
11-14-2012, 12:38 PM
Good job! Yes my HV were barely visible in reflections too, that was the big time saver. Glad it worked.:beerchug: