I use my vast collection of textures & personal photos to use as overlay layers in photoshop. You can apply different settings to the layers to acheive different effects. I also create objects & materials from scratch, using a combination of painting, filters & effects. I still haven't quite figured out how to get Photoshop or Bryce to fetch coffee, but it's comin,  and I can get them to do everything else imaginable.

The trick to using gray rendered objects is that it's a neutral canvas with enviroment effects already added, IE: shadow, highlight, reflection, etc. ........and you can alter the depth of the grayscale to accomodate desired manipulation.

If anyone's interested I can post some basic "How to" scenes, there are different styles & approaches.

Let me know

....it's mostly just knowing your software inside & out. (and then respecting it in the morning)

Rod

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Ockham's razor- It's that simple