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View Full Version : increase "spread" of grey-scale Z image


slipster70
08-18-2005, 04:39 PM
Good morning.

I need to increase the "spread" or range of my Z-buffer grey-scale image. Is there a setting to tweak for this? Perhaps camera aperture or zoom factor?

I remember reading a thread about using fog and the alpha channel to really control the depth of the grey-scale image. Is that still the best way?

Thank you.

slipster70

MooseDog
08-18-2005, 08:36 PM
change all your objects into black matte objects, put a white bg into the scene and add fog. from there you can control exactly how much fog there is, from right in front of the camera to however far away you wish, plus, if you want, different types of falloff for the fog. crank up the aa and let'er rip:scream:

gerardo
08-19-2005, 02:12 AM
Good morning.

I need to increase the "spread" or range of my Z-buffer grey-scale image. Is there a setting to tweak for this? Perhaps camera aperture or zoom factor?

I remember reading a thread about using fog and the alpha channel to really control the depth of the grey-scale image. Is that still the best way?

Thank you.

slipster70


That depends. If you are extracting your depth buffer from a RPF/RLA for example (Extended RPF/RLA Export), you can adjust the "spread" of this buffer in a compositing sofware (black point / white point). If you are using common formats, then you can use Render Buffer Export (normalize option), or for more versatility, you may use fog (as Robin says) or a same gradient in all surfaces (although fog is more easy to set up)
Remember for a depth pass is better to avoid the antialiasing and to render your sequences at quadruple of resolution. Besides being faster, you won't have problems with artifacts or subpixels :)
(btw, I guess you are talking about control the gray scale tonalities and not about to increase image bits)



Gerardo

jorust
08-19-2005, 08:11 AM
You can also try this method, using FPrime

http://www.spinquad.com/forums/showthread.php?t=7451

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