# Alpha channel enable?
**URL:** https://forum.highend3d.com/t/alpha-channel-enable/60782
**Category:** Xsi
**Tags:** rendering
**Created:** [January 9, 2002, 3:17am UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782 "2002-01-09T03:17:15Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@pomme](https://forum.highend3d.com/u/pomme)
#### Post date: [January 9, 2002, 3:17am UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782/1 "2002-01-09T03:17:15Z")
I've a .pic file which has alpha channel. How do i apply to an object so that the object can show the white area(alpha channel white area), and the black area tobe transparent. I should put that in more detail. My .pic file is for hair texture. The RGB channels are the actual hair color. And i add an alpha channel to that so that it can look more like hair cutting edge insteal of a flat piece of picture. In SI3D, i will make the object metarial totally transparent, and when i add the .pic to that object, at the texture window, i switch it to "alpha channel" at map component, and i will adjust the transparency slider to -1. so that the white area on my alpha chanel will show, and the black area will not. That is how I do it in SI 3D. This is what i want to do the same in XSI, however, i 've try pretty much everything. Any idea?
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### Author:  [@richard-sher](https://forum.highend3d.com/u/richard-sher)
#### Post date: [January 9, 2002, 2:56pm UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782/2 "2002-01-09T14:56:30Z")
There are a few tutorials on this page that will help you utilize the alpha channel. [http://www.edharriss.com/tutorials/tutorials\_materials\_xsi.html](http://www.edharriss.com/tutorials/tutorials_materials_xsi.html)[http://www.edharriss.com/tutorials/tutoria...erials\_xsi.html](http://www.edharriss.com/tutorials/tutoria...erials%5C_xsi.html)
Especially these:
Layering textures and materials using the alpha channel in SOFTIMAGE|XSI
Using and image with an alpha channel
Transparency Mapping
Using the Rendertree to blend shaders
Render Tree nodes in XSI
Mix2colors : superposing 2 opaque images
Ed
XSI Videos, Classes, Tutorials, Tools, Shaders....
Available at:[http://www.EdHarriss.com](http://www.EdHarriss.com)[http://www.EdHarriss.com](http://www.EdHarriss.com)
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### Author:  [@pomme](https://forum.highend3d.com/u/pomme)
#### Post date: [January 9, 2002, 7:07pm UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782/3 "2002-01-09T19:07:07Z")
Edharriss, thank you for your site. there has so many tutorials. However, I cannot find a tutorial that suits my case. please help.
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### Author:  [@richard-sher](https://forum.highend3d.com/u/richard-sher)
#### Post date: [January 12, 2002, 9:09pm UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782/4 "2002-01-12T21:09:51Z")
Plug your image into the color2alpha node, then plug that node into your material type's transparency input.
Ed
XSI Videos, Classes, Tutorials, Tools, Shaders....
Available at:[http://www.EdHarriss.com](http://www.EdHarriss.com)[http://www.EdHarriss.com](http://www.EdHarriss.com)
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### Author:  [@pomme](https://forum.highend3d.com/u/pomme)
#### Post date: [January 17, 2002, 4:06am UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782/5 "2002-01-17T04:06:06Z")
It works now. However, i want to make it apply on both side. Now it only works on the side that the normal is facing, not the back. I understand it is becaue of the normals, but is there a way to make it apply on both sides?
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### Author:  [@richard-sher](https://forum.highend3d.com/u/richard-sher)
#### Post date: [January 17, 2002, 5:08am UTC](https://forum.highend3d.com/t/alpha-channel-enable/60782/6 "2002-01-17T05:08:27Z")
You can either tell mental ray to render both sides (in the render options) or you can assign a "switch" node to your shader which will allow you to put a different texture (or 2 copies of the same texture) on either side of the polygon.
Ed
XSI Videos, Classes, Tutorials, Tools, Shaders....
Available at:[http://www.EdHarriss.com](http://www.EdHarriss.com)[http://www.EdHarriss.com](http://www.EdHarriss.com)