Physical Cam zoom -> connection with focal lenght

[Antimatter]

I would like to see a connection with zoom and focal lenght of the c4d-camera.

I did a setup for myself with Xpresso and two cams.

One cam for setup the zoom and one (physical) for rendering.

How about one switch so we can connect the zoom with focal lenght.

zoom factor 1 => focal length 36
zoom factor 12 => focal length 432

I've uploaded the Xpresso Scene ... it is not possible to connect
the zoom with focal leght on one cam, because then vray is adding
zoom to the focal length.

http://www.art-3d.com/vray/camzoom.rar

cheers,
christian

-
www.art-3d.com
www.kunz-av.com

[stefan]

the zoom in phycam is somehow redundant, it is better to use the c4d cam zoom i think.

they are basicly the same. we probably should hide the phycam zoom to prevent confusion.

cheers
stefan

[tcastudios]

Stefan I think I replied to this at another thread as well.
I'd very much like to have the Zoom still there just because it is -not-
connected to the focal length. The description for the zoom in Max is that it acts as a magnifier and this is very good for re-rendering out parts parts of a fullrender (in combo with filmoffset and render pixels related to the zoom value. I even have a rig set up just for that).

Also the Perspective Cinema Camera have the zoom disabled (greyed out)

Cheers
Lennart

[stefan]

by the way, we have a full render region feature in vray!

just render the are you want. under system in render options:-)

1) render the region in viewport
2) activate the render region in system tab
3) render in full size. vray renders the part of the image in full size.

much easier, no need for zoom for this.

cheers
stefan

p.s still changing the focal lenght i am very confident is exactly the same as a zoom. the perspective lines doesnt change. i used that in old times in c4d for exactly that.

[tcastudios]

stefan wrote:
"p.s still changing the focal lenght i am very confident is exactly the same as a zoom. the perspective lines doesnt change. i used that in old times in c4d for exactly that"

yup, it's the "same" for a Regular Cinema Camera as long as correctly calculated DepthOf Field is not used. I have so far only the Max info to go on that "Zoom is the same as a blowup".

Using a VrayPhysCam this is good, because changing the FocalLength do change the DOF.
In my case/tries I'm not interested to get a full render of a region, rather a pixelexact region render. This is to re-render parts of a render, including moving objects.
That would of coarse be much easier when/if there can be a "Not Calculated By VPCam Comp Tag" that can be applied to a plane in front of the camera.

PS. Renato maybe can at least keep it accessable in the res.h file? :)
I suppose its ID can be used even if it is hidden? DS

Cheers
Lennart

[stefan]

ok you are right with dof. yes.

still you can use our render region feature, that is really a crop, also woth dof, phycam and all.
it is even animatable.

cheers
stefan