I suspect this was created for one of Dad's slide shows. He took up photography in the 1960's with his first purchase of a SLR. I remember visiting him at his home where I found little notes lying around with scribbles showing calculations of f-stops, shutter speeds, lighting angles, etc. Curious, I once asked him what that was all about, and he told me that he was getting older and worrying about gradually losing his mental abilities. He was a believer in the "use it or lose it" philosophy.