I have hundreds of old medium format slides from the early 1960's, that I shot using my Rolleiflex camera. Many are very precious, & in some cases, historical, as to locations, etc. I ended up building the stage set-up shown, & along with my current digital camera, a Sony DSC H-7, was able to copy the original slides, using a tripod, & the camera set in macro mode. Fortunately I am able to edit every slide on my "Mac" computer, without using photoshop. I am extremely satisfied with this procedure, as many of the color slides were rapidly deteriorating. I don't know how other computers compare as far as iphoto editing goes, but I'm so very happy with the results.
Hope my diagram is pretty much self-explanatory to all.