In this attached image is the shader for a plane. I'm trying to see what settings are needed to get a Poser hair texture/transparency map combination to work at least as well in Carrara as it does in Poser. But no permutations of the shader options have worked yet.

In this attached image is the render of the plane with the tex/trans shader. This plane has shadows turned off, and is about 5 inches in front of a green plane that is 150% larger. As you can see, with or without "light through transparency" in the renderer (ray tracer), the transparent areas of the smaler plane tend to multiply (lighten) the color of the green plane behind it. The result is much worse if shadows are turned on, or if the transparency map is darkened. Changing the ambient from 0 doesn't seem to matter much, nor do variations in backface settings nor variations in reflection, glow or refraction settings. My question is: what settings do I use to avoid the lightening of whatever is behind the transparency?

Transparency is really uneasy in Carrara ... Look at this shader tree . I've used a multi-channel mixer with a fully transparent shader in source 1, the main shader in source 2, and these two shaders are mixed by the transparency map . I hope it helps . litst

This Mixer technique works well for your papillon. I shall give it a try. Perhaps my method was causing the textures of planes 1 and 2 to interact, or mix, somehow. I see the advantages of your method - it doesn't require inversion of the Poser transparency map, and it allows intuitive gradation of the degree of transparency.

Isn't there a subtle distinction between transparency and alpha? I think transparency means see-through-ness whereas alpha means is it there or not. Then there's translucency to complicate matters which I think means whether or not a backlight can cast an image of itself on the material such the image can be seen looking at the front of the material. One of the things I've been playing around with in different apps is putting a bulb light inside a sphere and then seeing if you can see any light seeping through the sphere surface (from the outside) with different transparency/translucency/alpha settings. The result seems to vary somewhat between apps.

In the image above, I used Litst's method for the hair, which had to be a vertex primitive to avoid strange transparency artifacts involving the backfaces. The head had to be facet meshes to avoid more subtle artifacts. Details like the eyes, brows and lashes were more straightforward, and did not require the multi-channel mixer method to get useable transparency. Hartcons, regarding your idea, it sounds interesting. I'm no expert, but for me, the alpha channel is a post-render effect that can be used as a transparency mask in a 2D program like Photoshop. The transparency effect in Carrara can probably produce such an alpha channel in post-render, but it's also a stand-alone 3D effect.

In some 3d programs you can use alpha to alter geometry. Let's say you want to have a bunch of star-shaped holes in a sphere for example. You can apply an alpha texture map of black stars on a white background. Then if you put a bulb light inside the sphere and turn on volumetric/cone lighting the light will shoot out through the the star holes. Making the stars 100% transparent (not an alpha) is different but maybe in some programs amounts to the same thing. C4D for example has separate transparency and alpha channels in its material system. Lightwave has an option where you can say that a texture map is an alpha (and I think this can happen in any channel that accepts texture maps). Carrara's G-buffers are handy in that you can do things with the alpha mask in Photoshop as suggested in the previous posting. Some programs allow you to render in multiple passes to facilitate compositing in Photoshop or After Effects (I've been surprised to see how much "3D" work is actually done post-process in Photoshop).