While I have
seen some colour transparencies, it's unusual to me to be seeing a black and white one. What were transparencies
used for, anyway?
Transparencies were primarily used for press packets for major newspapers and magazines. The bigger the medium for photographing and reproducing the photo, the higher resolution for, say, a Life Magazine cover. 2x2 slides and 8x10 clossies need not apply. My Alamo press kit included tons of 8x10's and a dozen or so 4x5 transparencies. The 8x10 glossies would have been blown up from a 35mm. camera negative. The 4x5 transparency was photographed on a 4x5 negative. My kit also has a color transparency of the Reynold Brown painting that is maybe 4x12. All are color-shifting to the red end after 50 years.
Notice, the black and white photo above is backwards (see belt buckle and Duke's watch on the wrong wrist). This often happened when printing from a transparency with no indication of front/back. I had to make a Pennsylvania lab take three swings at the ball when printing the shot of the Mexicans storming over the barricade toward the Alamo chapel because they kept printing it backwards. They kept swearing that they were observing the emulsion position on the transparency; I kept insisting that I knew it was backwards BECAUSE I USED TO LIVE THERE!!!!!