Matt,
A good formula for reference is taken from Shep Paine's book on dioramas.
That being that the aprox. distance you can focus your eye on a figure is about 5". At that distance a 1/35 scale figure appears the same size as a man about 20' away. A 120mm or 1/16 would be about 9'.
Forced perspective can be a pretty cool effect for dioramas, but you have to control the angle and direction the viewer looks. A slight change in angle and the effect is ruined if the eye can get a relative sense of scale and depth of field.
Good luck with your project.
Mike
"Imagination is the dye that colors our lives"
Marcus Aurellius
A good friend will come and bail you out of jail...but, a true friend will be sitting next to you saying, "Damn...that was fun!"
