Matching parallel camera zoom to C4D viewport

[Grum]

Hi all,

I've been working with the Parallel camera in Cinema 4D and noticed when the zoom is below 1, the viewport in Cinema does not match the Octane live viewer, or final render to picture viewer. I was needing this to be a low value in order to render the entirety of an object in parallel view.

After changing some things around I found I could make it match if I changed the focus distance. However I could not seem to find a simple function to link the two. In fact, trying out some values to match viewport to octane it made this graph of zoom value vs focus distance.



Is there something I'm missing here? What function do I have to apply to zoom in order to get the focal distance to match Octane's output to what I'm seeing in the viewport.

[Grum]

Just to put a more understandable visual to this, here are some screen grabs of zoom vs focus distance for different values as shown in the graph above.

You can also download this file for a quick test here:
https://www.dropbox.com/s/tm71um0l8aknr ... t.zip?dl=0

Zoom 1, focus distance 2000


Zoom 0.5, focus distance 2000


Zoom 0.1, focus distance 2000


Zoom 0.5, focus distance 1850


Zoom 0.1, focus distance 44.5



If this is the expected behaviour this is fine, but I want to create a tangible Xpresso script to link focus distance to zoom and I can't work out what that is just now.

[DinoMuhic]

yeah I noticed the same and also eye-balled the cam using the focus.

I asked Ahmet about it and he said Parallel Cam is just not yet supported in the plugin. What we have now is just a workaround to have ANYTHING at all.

I wish he could find time to make it work the way it has to. At least I'm not alone with this issue and I need parallel cam rendering really bad.

[Ibycus]

Yeah, this is annoying. Would love a fix to this also.

[lukas8410]

Damn it, so now I know why my I am experiencing differences between render in Octane vs C4d native.

It makes things a lot harder, because what I am trying to do Is to get precise scale. I want to render a game board, which would be divided on certain number of squares in a grid manner,
and I need them to be lest's say 70px each. I've figured out how to do it in c4d native, but now it gives me entirely new level of hardness. Can anyone of You help me with understanding how could I achieve such task?

I've got zoom 32, so what should be the focus distance?

Also the grid rendered in standard, does not match with elements layed on it exactly to the scale when rendered in Octane. I'm not sure what can cause this.

Luke

[Grum]

Since making this post I've discovered that the standard octane camera is also poorly matched to the native renderer and there's no way of keeping an accurate scale. I had to make sure my post process only used Octane output for diffuse colour, AO, etc.

My attempt at a workaround on the parallel camera by doing a telephoto lens from further away resulted in a dramatically different scale too, and so I can only surmise that the math is completely wrong for all cameras in C4D Octane.

I'm unable to test in the absolute latest version of Octane as R14 support was dropped about 2 versions back...

[lukas8410]

I'm not sure about Your case, but i was able to find something that works perfect for me in standard, even tough it's useless for rendering in Octane. But still check this link, maybe You'll find it useful somehow:

https://www.c4dcafe.com/ipb/forums/topi ... ntry359726

Cheers,
Luke

[VVG]

yes. i have similar problem with Frontal camera

viewtopic.php?f=30&t=68686