View Full Version : Z-depth for focus-blur.

08 August 2002, 01:26 PM

Is there any way in combustion to use the z-depth channel for the intensity of a blur?

08 August 2002, 04:38 PM
composite the original image over itself and then import the seperate z-depth map as footage only or bottom layer. apply a discreet keyer to the top layer and then use the z-map as keyin, set the range to HLS and disable the Hue and the Saturation. This lets you define a range (using the tolerance settings in the keyer) in which the top layer of your image is transparent or semi-transparent. now you can blur the top image as much and in whatever manner and finally get your depth of field. if you need soft gradients for your focus this might need some tweaking in the keyer but it will sure work!
iīm also almost sure there must be some way to achieve a DoF using RLAs but i really donīt know? maybe someone else?

08 August 2002, 02:21 PM
if you render out to and RPF you can run an RPF DOF operator. This is an excellent way to achive soft focus based on z-depth


08 August 2002, 06:48 PM
How do I render to RPF files, there's no such format in maya...


08 August 2002, 07:12 PM
Originally posted by kamsvag
How do I render to RPF files, there's no such format in maya...


Does maya render RLA? If not you can render a depth map and use a compund blur. Also try lenscare (

08 August 2002, 11:00 PM
Maya doesnt render rpf or rla, but it does render Z-depth. I'll get back if I get it to work.

09 September 2002, 06:49 PM
you could try to duplicate your layer in combustion and make it a grayscale image. place it under your original footage. add a compound blur to your original footage and choose the grayscale layer as your source, you may want to tweak the levels of your grayscale image to achieve the result you want. it's not true z depth but it is a great way to fake it. give it a shot and let me know if you need any more help.

09 September 2002, 10:57 PM
Okay so you wanna create Zdepth in Combustion with shot's rendered from Maya..... If I understand you correctly.
Well if you turn of all your Lights in Maya and then go to renderglobals and turn on the enviroment fog, you should be able to see your objects in black and white. YOu can tweak the fog like a ramp. keep in mind what ever is white will be in focus and what ever is black will be out of focus.
Render the shot as a targa, and then render it with the fog turned off. Take both Images into Combustion, open the origanl one apply compound blur. In the compound blur you can source your footage, source it to the fog render. Split the screen, one view of the origanal and the secound of the alpha fog render. Apply the colour correction operator this gives you the ablity to change your levels on the alpha alowing you to change the range of zdepth.
Sounds complicated but this is really easy actually.... and verypowerfull tool as well.
hope this helps

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