You could use grayscale materials on all the objects with or without grayscale texture maps. For example, use a medium gray diffuse color for some objects with no texture maps, and just add a bump map, and as long as you don't have any colored lights in the scene, it would render gray tonal.

If you wanted to use texture maps, you can use those already out there in color version, just convert them to grayscale in photoshop or the like. That would most likely reduce the file size of each map somewhat, which would aid in render time.

The render time difference would depend on the file size of your texture maps after being converted to grayscale, but not much else would come into effect here. Things like changing the diffuse color without any maps attached doesn't impact render time. As far as I'm aware, the renderer doesn't care if the diffuse color is black, white, or red. It's the texture maps that add on to the render.

"In otherwords, what if a film maker wanted to make a black and white film?"

The easiest way is to just shoot the scene normally, and desaturate the whole thing in post. AfterEffects, etc. Again, you could desaturate every texture of their color before hand, but that's up to you. It might not make that much of a difference in render speed, depending on the file sizes.

Message edited on: 02/15/2005 02:19

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Tools :  3dsmax 2015, Daz Studio 4.6, PoserPro 2012, Blender v2.74

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