I was curious if someone could fulfill my curiosity regarding this subject - I have a scanner, but I don't have a decent mirror to try it out with (as mine are all mounted to the wall).

Put a negative on to be scanned, but instead of using the light which comes with your scanner, instead use a mirror so the light from the scanning head reflects back.

If you could post a comparison between the mirror method and the back-lighting method I'd appreciate it.

Unless it is a frontsurface mirror and if it works.. wouldnt you get something akin to a double exposure because of the diffraction by the depth between the glass and the mirror surface.. also you are not getting reflected light.. you would be getting light that has been initially filtered by the negative then bounced back through the negative again.. Just my random thoughts... Then again.. maybe it will work

Well, SOME scanners have a VERY limited DOP (Depth of Field). However I recently dismantled one that not only had an insane DOP, it also had a pretty impressive light sensitivity.

I guess it depends on the scanner, but I can definitely see ghosting being a problem - although I guess you could frost/glaze the mirror if it's not an important one.

However, so far as light quality goes I guess my only concern is being able to do produce usable scan on the cheap (I.E.: Without a lighting unit).

It may seem like cheating but when I had a few negatives to scan I just cleaned them good and went to WallyWorld and had them printed and put on disc

Enough of my silliness... I am going to bed!! Someone give this OP a decent answer...