[and]

Just realized something that I wasnt aware of. I was playing around with a lens indoors that had a min focusing distance that was too long for that room (4 meters) but suddenly I had something in focus: the camera in the mirror.

Turns out the focusing distance when focusing at the mirror was the distance from the camera to the mirror x2, so not only was I able to get a picture in focus with that lens in a small room, but I even had to set the focus to 6 meters to do so.

Just a random trivial fact, tho I thought it was interesting since I had never realized that before and I probably would not have if it hadnt been for the fact that I knew that lens should not be able to get anything in focus, normally I dont check what distance the focus is set to.

btw in that regard it would be both cool and usefull to have the camera display the current focus distance of the lens in the viewfinder!!

[Rolly]

Yup.

Think light, not camera, and suddenly it seems 'Oh! So simple.'

(In your example the light traveled from the subject and bounced off the mirror before finally arriving at the camera.)