Quest,

I have to disagree with your statement that "most artists that create models for general free consumption often ask to be accredited". I have very rarely found that to be the case. But, in any case, I clearly stated that I was referring to free models "with no strings attached". I would consider asking to be credited a string (which I would honor if I chose to use that person's model). I would urge all modelers who want to be credited every single time their models are used to very clearly state that.

Assuming there were no crediting requirements specified by the model creator:

If I took someone's model of a spaceship & plunked it down on a starry background (which, btw,  I would never do), I would feel obligated to credit them. If I used someone's model of a window & used it on a house that was a relatively minor part of the background of my composition, I probably wouldn't feel obligated to credit them. There are a whole range of cases that fall between those two extremes & I think it's up to the individual artist to determine when to specify credits. If the models are a very prominent part of the image, if I use multiple models by the same creator or if I often use models by a particular modeler, I will credit them - both to offer my appreciation &, as you suggested, to avoid having viewers get the mistaken impression that I created everything in the image from scratch. As an example, in my case, I have often used both free models & purchased models created by MatCreator. They have become part of my tool chest & I almost consider them as primitives in the same way I think of spheres, cubes or metaballs. I periodically credit him, out of appreciation, but I don't feel the need to do it every single time.

And finally, I have never claimed that any image was "entirely" my own or tried to create that impression. There is a tradition in art of using external sources without providing explicit credit. Pop Art used images of celebrities & commercial products (Campbell's soup cans), Surrealist collages used images clipped from books, magazines & newspapers, the current crop of Pop Surrealists use images from tv, movies & popular culture & modern sculptures often are constructed with manufactured components. Picasso said "Good artists borrow. Great artists steal". That may or may not have been said tongue in cheek & I'm not comparing myself to Picasso or claiming to be a great artist - I just don't think it's necessary to credit the source of every component of a piece of art.

"Every child is an artist. The problem is how to remain an artist once we grow up." - Picasso