• Maxon Cinema 4D

  Alpha channel problem

  Posted by Jack Cook on November 16, 2005 at 11:27 pm

  I can’t get the Alpha channel to work properly (or at least, to work the way it always has in the past). I’m using Cinema 9.1 on a Mac. I have a relief object and have mapped it with a Photoshop file that is a grayscale height map. That part works fine.

  The grayscale map has height information that doesn’t go all the way to the edge, so it is surrounded by black, which becomes the lowest part in the terrain. I want to cut this part out with an alpha channel and have only the terrain info, so it looks like a terrain with an edge. I’ve made an alpha channel in the Photoshop file, put it into the Alpha channel in a material and mapped it onto the relief. With Image Alpha and Soft checked (the default) there is no alpha cutout. The only way to get it to cut out is to un-check Image Alpha (in other words, to not use the alpha channel in the image). Then it cuts out, but the terrain becomes transparent. In the material there are only color and alpha channels, no transparency channel. I have done this many times in the past exactly this way to get the type of terrain I’m talking about, and it’s always worked. I can’t figure out how to fix this. I’ve been using version 9 for about 6 months, and I’m wondering if something is different in 9 than in 8, which is what I’ve done this in before. I’ve been through the manual trying to find anything, but there’s nothing different there.

  Anyone have any ideas about what’s going on here?

  thanks,
  Jack

  Jack Cook replied 20 years, 8 months ago 1 Member · 1 Reply
• 1 Reply

• 

  Jack Cook

  November 17, 2005 at 1:15 am

  I think I’ve found a solution. I made my Alpha map in Photoshop CS2. I tried it again in Photoshop CS, and it worked the way it should. So, it looks like Cinema is not compatible with Photoshop CS2.

  So now I’ve got the parts I don’t want cut out with the alpha. The only problem now is that the edges are not clean. Where the alpha cuts the edge, there are sort of “icicles” hanging down, which are the sides of the terrain. I want to eliminate those and have just a clean edge. Any ideas on how to achieve this?

  thanks,
  Jack

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