Yes, the aesthetic effect *would* be different.Originally Posted by bmac
Framing and matting is nearly an art unto itself.
I will confess to being partial to dark grey - I think Nielsen has a frame color called "gunmetal" (although most firearms are finished with dark blue) that I like very much ... my close second choice is black. My matting of choice has evolved to a black "main mat" with a white undermat. Generally. Exceptions to this are not rare.
All one can do is to look at the framed and matted work and decide for oneself - in that mysterious area called "aesthetics" - whether it "works" or not.
All I have been able to do is to visit the galleries, and after the usual "trying to leave the intellect (Hah!! - As if I had any!!) and opening myself emotionally to the work" ... I study, quite closely, any interesting example of framing/matting, with the idea of future application to my work.
I guess this is a non-answer ... but, no, I don't know of any "formula" or "rules".