View Full Version : Question about multiple alpha channel export

05-10-2005, 12:40 PM
Is there a way to create a compalation of surface alpha channels into one document. Or can this be done without manually clicking on every surface alpha and exporting them seperatly.

I would like to be able to render the final image and have an alpha channel saved for each surface for color editing or surface changing. So instead of one alpha channel, I would have one for each surface.

What's the easiest way to do this?

05-11-2005, 08:44 AM
Ok, I thought I knew more than I did. I want to render alpha only on a specific surface. I have messed around with Use surface settings in the object properties and tried several settings for the surface as constant value alpha 0-255. I get either an all white all black or the alpha for the entire object. How can I render just the alpha for a single surface? I'm sure there is a way.
Thanks again,

05-11-2005, 08:25 PM
If you want to save the alpha only, select render options. Select output files tab. Then mark save alpha give it file name and change the file type to whatever you wish.
To render the alpha only press F10 not F9. If you want the alpha for only one object, make sure the other objects are not visible to the camera. This can be accomlished by selecting properites for each object and mark the unseen by camera, or set desove to 100% for each object, or open scene editor and clear the checkmark to the side of each object you don't want the camera to see.
Hope this helps.

05-12-2005, 01:04 PM
1. If you want to separate objects in an image for color correction, render a pass with all the objects 100% luminous 255 red, green or blue. For an additional channel, turn off alpha for the rgb colored objects and make your fourth set black with the alpha on.

2. You can set alpha options per surface in the advanced tab of the surface editor.