Quote Originally Posted by wildbillbugman View Post

"reflected 90deg away from the centre which is left unaffected ..."

Reflected off of what?

Front surface mirrors - the thinner they are the closer you can get them to the 2 pinholes ...

Thinking about it now you wouldn't have them lined up - better to have them forming the 3 points of equilateral triangle so the distances between any two arbitrary holes were always equal.

Maybe you'd want to use 3 mirrors - the camera would end up looking kind of 3-way symmetrical (what is the correct term for that?) - sci-fi !