OK, so JOHN'S "Academy" aperture dimensions (.825/.602) CONFIRM that the correct official aspect ratio for non-widescreen sound prints IS indeed 1.37:1, and in line with all the info I had previously seen about this... In the "real world" I have seen widescreen flat pictures projected from approximately 1.5:1 to 2.0:1 with results varying from quite satisfactory to just passable... With the nearly non-existant frame lines on most flat prints nowadays, you have a LOT of latitude between having the mic showing and losing major verticle information on widescreen flat pictures, and few installations are EXACTLY 1.85:1... Unless you are showing a great many older classics in the 1.37:1 format, you will probably be able to use your normal flat aperture and lens on the rare occasions that you show an oldie... Only the purists will even be aware of it because the public sees so many films on TV that are modified from their original aspect ratios...