VRayZDepth link to phys. cam. f-stop

[re:FORM]

Hey Vlado,
It would be really great if you could add an option to make the VrayZDepth parameters match the current VrayPhysical Camera focal information?

That way we can preview dof using vray (low samples) then render out without vraydof and then add dof in post using the z-buffer. It would also allow visual testing of animated dof in the viewport.

[Da_elf]

ill second this as well. nice one

[re:FORM]

We could set this up manually if there was some way to access the depth of the camera focal gizmo and then wire those distances to the z-depth parameters in the render elements panel.
Vlado, is this a quick workaround that could work? Are those values (camera focal planes, and render elements z-depths) accessible in maxscript?

[studioDIM]

Through max's renderelements interface you can access VRay's channels.
Through the camera you can check where the focal POINT is, but nor the min and max focal ranges.
In fact, those DO change not only with the F-Stops but also with the vertical shift and distortion (not the focal point, mind you, but the focal ranges' "tips").

Some nice mess you got yourself into, there :P

Lele

[studioDIM]

Reread better what you want to do, and sorry to come out like this, but i think it's useless.
Save a FP Z-buffer, in post you can change it in realtime (levels.).
That's exactly why you would want to go post in the first place...

Lele

[re:FORM]

Yea, I know what you mean

I think I was just trying to link the dof in post to something that I could see in max, rather than having to set the z-buffer to something fixed that I then animate in post with levels.

If I understand you correctly, then if I was doing a shot where the camera is moving towards the subject, then I'd have to carefully adjust the levels in post so that the focal point remained on the subject.... ..... not something I want to do manually in post...... whereas I want to keep the z-buffer value on the subject fixed (say 12, and the levels on either side to change accordingly. If I'm dollying towards the subject, then the near and far values need to change in relation to the camera movement to keep the subject in focus Ofcourse, you can do focus changes on top of the changes recorded out from max in post by changing the levels, but I'd only use that if I wanted to change the focal point without re-rendering the z-buffer.... but any changes would still be relative to the fixed focal point as produced by having sliding near and far values. (argh I think this probably makes no sense whatsoever!)

or maybe I'm missing your point?

I guess another option would be to have the following options in the z-buffer render element options.

focal point = camera target
z range (focal depth either side of the focal point) = either a distance, or could be based on the vrayPhysicalCamera ranges as defined by f-stop, vertical shift, and distortion.

[studioDIM]

The Z buffer contains only depth informations, not DoF ones.
Ie., it is correct when it contains values which go from 0.0 to 1.0.
It's a post filter problem, more than anything else.
That is, you'd just have to animate in near-realtime the parameters of the DoF filter in your post app.
Combustion's has near and far ranges, and blur amount.
They are keyable, have proper splines with all sorts of interpolation to govern their behaviour over time, and work in realtime or thereabout.
Key is to have it in FP, though, especially if scenes are particularly detailed, big, or in large formats, as otherwise errors might be introduced (in combustion. other things might work exceedingly well with less requirements).

Hope it helps

Lele