The manual book that came with Carrara 3 have very little information about alpha channel. I tried to put leaf texture map with the tree in Carrara 3. It did not remove the background. I put either full black or white, c3 still will not remove transparent it. I rather not to use adobe photoshop because I have thousands texture to import in. Most are with alpha. Did you have any success with alpha channel? Thank you in advance.

Sorry to break the news to you, but you will have to use Photoshop. The alpha channel should be pulled from the tens of thousands of textures you have lying around the house and placed in the 'transparancy' channel of the shader, eh, tree. When you import your humongous amounts of textures in the color channel it just takes from the bitmap what it says, the color. In photoshop you could make an action, I think, to process small batches of your biotanical collections. An action would leaf (sorry, leave) you with a new document per texture, that should be saved by a describing name (like 'SouthChineseScholarTree-ALPHA') which I think is not possible in PS. What need to be done is that in the 'Channels' tab you select the channel, choose 'Duplicatie Channel' from the tab menu and choose 'NEW' in the following dialog box. This creates a new document that can be saved as a grayscale bitmap, to use as an alpha. Because there are so many textures involved you should maybe only use the ones you are actually going to need. Unless you are making an Encyclopedia Of Trees Around The World the workload should be overseeable. Good luck with it!

I think Waldo is asking how to map a custom leaf texture onto whatever shape is used with one of the Carrara trees. Custom leaf files are mentioned on page 71, but no details on how to apply the maps AFAIK. So you would have to do a leaf.car file with the standard transparency mixer shader tree, as described by Antoine et al. in previous posts in this forum.

Waldo, Currently I'm working with the tiff format which offers multible images in one file, but a true alpha channel would offer 8 bits to use as masks (black/white) for such things as transparency, specularity, refraction etc. In other words a 24 bit file would have an extra 8 bits making it a 32 bit file. As I don't know that there is a standard for so called alpha channels I don't know that what you do in one application would translate properly to another application; it is an interseting topic and one of which I've meant to explore further for some time now. In my case, a detailed exploration of this topic as concerns your question might have to wait for an upgrade to C3 which will be a while for me yet, but I'm probably as interested as you are in the answer and in what others may be able to offer up in this regard. If C3 uses "alpha channels" in the same way as Bryce does, you may need a seperate pict, bmp, what have you, to use as an alpha channel. cheers, - TJ

Well Eovia announced that they improved Alpha Channel when they released C3 If I still have to use B/W map for transparency then it mean that they did not improve alpha channel in C3 at all

Bikermouse, VUE and Carrara only need either full black or full white in order to make a transparency. VUE can take in 1 image map with leaf and full black or white in background outside leaf area. VUE will make it transparent automatically. Carrara3 should do the same and I expected that it work the same as VUE after this release announcement.

Do you have link to tutorial how to create BW for alpha map in photoshop? I forgot how to do it.

Waldo, I just use the magic wand tool and set the tolerance so that what I want to mask is selected in conjunction with the invert selection and fill tools - this might take a little fiddling around and it doesn't always work as well as you'd like. You just make your object black and your mask white and that's it. if you need to invert the mask colors use the invert option. If you are working with multible layers flatten the image first and remember to work with a duplicate file so if you mess up nothing's lost. - TJ

If there is an alpha channel present that is all you need. I already lined out what to do. [snip] What need to be done is that in the 'Channels' tab you select the channel, choose 'Duplicatie Channel' from the tab menu and choose 'NEW' in the following dialog box. This creates a new document that can be saved as a grayscale bitmap, to use as an alpha. [/snip] You do not have to use the magic wand tool. You should not use it, because it is not very precise, so you would end up with white borders around your leaf image. The way the shader tree of Carrara is organised does not keep the option open to use alpha information that is present in a Photoshop or TIFF file. When using masks on leaf shapes you should not forget to look up some threads about transparancy around here. In the part of the leaf that should be invisible there should be absolute black in the color channel, black in the alpha channel and 'light through transparancy' should be ticked. It is also possible to use custom shapes for the leafs, what is a nice alternative too, because it shows with the most simple render methods. Have fun!

Quote - Because there are so many textures involved you should maybe only use the ones you are actually going to need. Unless you are making an Encyclopedia Of Trees Around The World the workload should be overseeable.

Well Actually I have whole XFrog Plants Library (19 CDs) Around the World. :)

...and you want to make the Carrrara Plants Library Around the World? Then maybe you should call someone (like Eric from the Digital Carvers Guild) to come up with a plugin that can actually use alpha channel information. Maybe it is an idea for a plugin? Anyone?