Z Depth map gives white only

[aggiechase37]

Can't get a grey scale out of the z depth map. Only outputs white. Brought into After Effects to play with exposure but still only white. No greyscale detail. What am I missing?

[stratified]

Try playing with z-max. Z-max defines which depth is mapped to white in a tonemapped image. Every object that has z further away than z-max is mapped to white so try to increase this value. As an alternative, render the passes untonemapped which stores the original depth value.

cheers,
Thomas

[aggiechase37]

Thanks. Any good heuristics for what z-max values typically yield good results?

[stratified]

There's not really a heuristic here - you only need to make sure that the z-max is larger than the z-depth of the object furthest away from the camera in the scene. You will need to fiddle with the slider a bit to figure out this distance. The z-depth max is only there to normalize depth values so that they can be stored in LDR images. It's a hack.

If you want to be correct, you need to save your depth pass in EXR (disable tonemapping and use color space linear). In this case, the values in the EXR will be the original depth values of the scene instead of normalized values.

cheers,
Thomas

[aggiechase37]

So exr is the way to go for z depth passes. Learn something every day. I'll give that a go. Thanks so much.

[aggiechase37]

I give up. Tried variety of z depth max, tonemap, not tonemap, exr, not exr. I either get complete black, or only white objects. If I render a single frame it seems to work, but the instant I render an image sequence it falls apart. Can someone end my nightmare? Hell I even tried to switch to the C4D physical renderer, still nothing. I'm pissed at this point.

[bepeg4d]

Hi,
it works as expected here, I have only disabled the "Overwrite kernel settings" option, otherwise the infochannel kernel can't do his job:

here is the 35 frame:

ciao beppe

[aoktar]

I have checked and working here. Also you use sometings wrong.
Don't deselect "Post Effects" and don't use "Multi-Pass Image" section for saving. You'll loose some features.

[aggiechase37]

Thanks guys. I got it working using the info channels kernel. It took quite a bit of messing around, but I'm good now. But certainly stay tuned for the next episode of chase is a nit wit.

[elisabettagiovi]

This z-depth setting is a constant pain in the A**... I know there is a workaround in overwrite kernel settings, but it always comes back, and I wish some of the next updates resolves this issue. It looks like it's not a big deal, but actually it is big deal for all of us that use z-depth for compositing. Cheers.