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cesario1212
10-01-2003, 12:25 PM
Okay, with all the turorials out there, I have found no one who really explains compositing in layers or rendering in layers. The biggest problem is that no one tells you how to composite or render out zdepth info. They just make mention of it and then leave this gaping void to be filled by your ignorance (no offense to those tutorial writers, because the rest of their turorials did fine explaining the other elements of multi-pass rendering).

So here's my Q, how do I composite zdepth info in AfterEffects (non production bundle)? I'm using LW 7.5 on a MAC with OS X.2. I have a handy little plugin that renders out z-depth info in all the file formats LW can normally render out any image.

So 1) what file format do I use, and 2) how do I use it in AfterEffects to control my gaussian blur over an image?

Also, do iff and rla images in LW hold depth info? And what is the difference between Delux RLA in LW and RLA_24/32?

Art-man

bloontz
10-01-2003, 12:48 PM
Newtek has a video in the DFX+ tutorials that shows how to save buffers into psd files. I tried it the other day and I think you need AE Pro to really use the depth buffer. At least in the tests that I did with photoshop things didn't look right. Let me know if you get good results with AE standard. I have a copy AE 4.1 but didn't try it.

Mylenium
10-01-2003, 01:50 PM
You can control depth blur with standard AE, however it's a bit more complex. First of all you quite likely will need 2 duplicates of your sequence in AE - one controls the blur directly in front of the camera, the other to control the blur in the far distance. Then turn those layers into asjustment layers and hide them (if AE does not automatically). Apply your blur(s) to those adjustment layers and put your RGB image underneath. Now manipulate the grey values to adjust the intensity of the blurring (white = 100%, black = 0%). Now you're done! The effect will not look like real depth based blur, but will be good enough for most jobs. Also take into account, that using adjustment layers will ruin alpha info on the RGB layer in most cases (even with "protect transparencies" enabled). Quite obviously for this the file format doesn't matter.

Mylenium

cesario1212
10-01-2003, 10:51 PM
I'll give your technique a whirl and let you know how it goes. Thanks much!!

Art-man

cesario1212
10-02-2003, 06:47 PM
Mylenium, with some minor adjustments to your idea it worked! Here is a sample image.

I had one rendered image pass for the beauty pass. I duplicated the layer in AE. I then had to use the zdepth as a luma matte on top of a "solid" layer. The solid layer was then used as an adjustment layer on the main background image/beauty pass. I took the layer I was using as the foreground image and used zdepth as alpha for it. The foreground was then adjusted using the same dual layer technique as the background. I simply tweaked the levels for the zdepth to adjust how much each matte revealed for either the foreground or adjustment layers. Did that make sense?

Art-man

JDaniel
10-02-2003, 08:18 PM
This can also be accomplished in Layout. Apply the 3 image sequences to a poly on 3 layers in the surface editor. The 1st layer(bottom layer) is the clean render. Make the 2nd(middle) layer by instancing the first and apply a blur filter under processing in the image editor to it. The top layer (3rd) is the depth map sequence you make as an alpha to the 2nd layer. Adjust the levels of the depth map sequence w/ the image editor for more dof control. You get the depth map in the psd export filter when you render the clean sequence out. Then you just rerender the frames on the poly. Hope that made since. :)

cesario1212
10-05-2003, 04:18 PM
yup, made plenty of sense. It's a pretty good idea. I'll keep it in mind.

Thanks!

Art-man