In my latest Bryce render uploaded here, I deliberately left off artist credits because I purchased those models a long time ago, and elsewhere. Ordinarily, I would type in the credits, but I felt onery that day because they were several years old, although readily available and I didn't feel like looking up the readme. Nobody ever asks me "gosh, who made that model" in my renders.

If I were using models I bought here, I'd use the crediting form that Renderosity provides. Two of those artists have taken the time to look at my renders and comment. I am well aware that this kind of art is a collaborative effort of many artists. When I use freebies, I always make the acknowledgements of who the artist was and where I got it so others can have access. I do that with textures, and poses too.

But if a model was purchased, does artistic ettiquette require artist acknowledgment? And, for how long? Really, in my example, the Millenium Dog, and the caravan and M4 and his M3 old hair and clothes should have had plenty of artistic exposure and mention by now.