I'm doing List tutorial about masking ( http://www.chez.com/litst/eng/tut-label/tut-label.htm )The toturial is about how to put a label on a can. What I would like to do, based on this tutorial, is to have the label masked WITHOUT the can. What I'm trying to do is to put a photo of a person on a plane with an alpha mask on it so that we see only the person without the plane... Not sure if I explained it right :P Now, if you can help me on this, I promise to worship you until the end of the world...even after. :) Thanx for your help.

You're in luck. It's pretty easy! Mark

Thank you so much Mark. I must admit that I spent some time trying to figure it out. You just became my new hero! :) Thanx again.

One thing to keep in mind when using the transparency channel to mask away unwanted geometry is that the geometry is still there. If you apply certain post-render effects to your scene, you may see the outline of the original plane. Also, if your lights are set to use soft shadows, the cast shadow will be that of the actual geometry - regardless of the transparency. Until Carrara supports clip mapping (using the alpha image to actually cut-away the geometry) You might want to consider tracing your alpha in illustrator and then making a spline object out of it. Then you could stick your image on it and it should fit perfectly. - Though you only need to go to this legnth if you have problems with the first method. -Scott

Attached Link: http://www.renderosity.com/viewed.ez?galleryid=384887&Start=1&Artist=songkann&ByArtist=Yes

Thanx Scott for your comments. No wonder I had some problems when trying to use lights with objects with transparency channel applied on it. I'll try to use your technique on my next project. Here is the WIP I'm working on with the transparency channel. The objects I used are pretty far away from the camera. Two picture of people fighting. Those pictures were mapped onto two planes. I could have used Photoshop to do it, but since I'm trying to learn Carrara, I wanted to do as much work as possible inside Carrara. And I have plans on using this technique on other projects too.

Attached Link: http://digitalcarversguild.com

For clip mapping, at least for fairly flat objects, try using the Anything Grooves. If will take a bitmap giving height data and generate an adaptive mesh for it. Normally the mesh is square/rectangular, but there is an option to omit the bits of the mesh where the texture height is 0 (black). Mik

You might also try using opacity with layers. It seems to remove some of the transparency artifacts, especially with partial transparency. With what you desrcibe as your goal, I have had great success using a two layer shader. The bottom layer is all transparent (color black, trans 100%, all else 'none'). And add a coverall layer with the channels as you want them except that I put transparency at value 0% and put the transparency texture in the opacity channel for the top layer. This seems to remove any of the fringing effects you can get with transparency. It works great for transparency textures imported from poser. Look for a subject line of "poser transparency" for an example shader. Marc