Why no Zbuffer saving in Blender?

We want to use Blender in professional work pipeline.
For this, we need to save Zbuffer, but we can’t. There is a filetype, called iris+zbuffer, but it is’nt work. I don’t found a program that can load it.

I’ve suggested this a couple of times, but no action. It really seems like it would be little trouble for an experienced coder to add a “Save ZBuffer” toggle to the render buttons, generating a second file for zbuffer info along with the rgb frame.

Ask over at blender.org.

Yup, I’m with you on this one too. Maya has that. The trouble is I only know one image format that supports depth information. Maya’s own image format (iff I think) does but the rest have to store it in separate depth files.

I think the best option is to use separate ones though rather than have a custom format because you’d have to make custom decoders for compositors. On a side note, I think the same for scene files. I think there ought to be a standard scene format for all 3D (probably in XML) like the Renderman spec so that a single scene file can open in Maya, Lightwave, Blender, XSI etc. Of course Maya would have to go trialware or something but conversion is such a pain.

Anyway, I’m all for the depth feature. It’s essential for high-end compositing. You could of course just render in layers in the mean time and do alpha-channel compositing.

I would agree… having the option to also output a depth file would be a great benefit. Lots of compositing stuff would be possible then. An example would be DOF could be easily applied to an animation after the frames were rendered. Making it faster and easier to control. Hopefully they can/will add this soon!

The “iris+zbuffer” file type does work and saves a .sgi This file type can be brought into Photoshop with the plugin available at http://www.telegraphics.com.au/sw/info/sgiformat.html

hope this helps.

i do agree that a seperate z-buffer save would be nice.

Why not just use the showzbuf sequence plugin?


you should be able to get the file you need easily with that

In my opinion the z-buffer should be at least 16 bit. So show-zbuf is no option. A 16bit psd grayscale would be fine.
But in the professional work pipeline I’m in, I’m having no trouble reading the sgi file format.

sorry for my english.

thx for the infos, I will try its

I use DFusion and it freezes when I try to load Blender’s iris+z file… :frowning:

8 bit grayscale channel not enough…

I’ve been playing with coding a different plugin and just for kicks made a quick little plugin that dumps the zbuffer into the image buffer (Including alpha). It really puts out a strange image so I don’t know if it would be of any use to you in this form but the zbuffer(all 32 bits) seems to be there. What kind of format do you need? Do you usually just use a 16bit greyscale? I can check into it further if you want…

we need a standart image format that professional compositors can handle

I don’t know what format will be perfect but I think there is many image format that can contains z information

Does anyone have a standard to suggest?

Iris + Zbuffer does work, and has a 32 bit zbuffer, but It is not supported elsewhere…


The IrisZ format is based on the SGI image specifications, compatable with it even. It is adding a 32 bits chunk to the RGBA chunk with depth information. We used this in NeoGeo for obvious zbuffer compositing or zbuffer effects yes. Unfortunately no other applications support it.

The zblur plugin has access to the full 32 bits zbuffer as well, it just displays it as 8 bits. You can just code any other method in this plugin, or export it to some format you would like.

Support for high definition color and zbuffers is ofcourse very important, but we also need developers interested to work on this… a very obvious candidate is adding support for 16 bits greyscale TIFF, as also used by ZBrush to save depth maps.

And last but not least, why didn’t anyone think of poking the gimp team to do something for Blender, like adding irisZ in their importers?
With the full 32 bits Z resolution in this format you can do very fancy things, not only composting but also DOF and edge detection for example.

ok, I talked with some guys from Gimp, and they are interested at least… first reaction was, it could be plugin, and using channels.

so their question is:

what would you do with the possibility of loading iris+zbuffer (or zbuffer in general) in gimp ?

so let’s hear all of them.
I write them down to their wiki then and let’s see what can be done :slight_smile:

(I already told them about DOF being one of the uses)


  1. Adjust the colour saturation and intensity according to the zbuffer value. ie. the more distant an object is the less colour you see. Great for landscapes as this is how our eyes perceive them.

  2. Zbuffer is also useful for masking out objects and edge detection.

  3. You can “tint” a scene (don’t know the proper term). Closer objects could have a yellowish tint while more distant objects could have a blue tint etc.

I would be happy if blender could render a greyscale zbuffered image easily. Here is a link to the work around I use for now:


I currently use 3DS for my 3D stuff and have been using the RLA file format which stores RGBA + Z buffer and other camera infomation. I don’t know much about this file format, but I am able to import it into After Effects and get all the DOF and other effects done in post using this info.

I really want to migrate to blender at home and then eventually at work, but without support for a universal RGBA-Z format it might be difficult.

I have seen some tutorials which show you how to fake a depth map in blender, and I will try these and see if I can make it part of my workflow.

Ok…so I dont really know where I’m going with this post, but my point is I really, really wish there was support for RLA…!

old old post.

if you look into the development we are adding EXR (or somthing like that) support, which is an image format that can hold many layers, with many different pieces of information for compositing, and post production.


it shouldn’t be too complex to have the zbuffer written to an image format, though an “auto save along with the regular render” may be tricky.

It’s probably more practical to just render the zbuffer in stead of the regular image as a B&W image… should be possible to render “quick” as well.

wouldn’t this kind of thing be included in the rendering by passes update to come soon? included as a pass, that is. or it could be.

You can store an arbitrary number of channels in a tiff file and have been able to for eaons now. This is not a problem.

You might have to split the zbuffer across multiple alpha channels in order to preserve the precision of blenders 32 bit(?) Zbuffer. This is conceptually simple though and has been done for years in other programs that save 32 bit displacment maps to TIFF by splitting the high precision greyscale data among the 3 seperate RGB channels.


A single 8 bit greyscale image is not precise enough to hold a copy of blenders zbuffer, which is 32 bits deep.