That ETR and Mamiya 646 came out around 1976 or so, to be a wedding man's 35mm. Fast and easy without the grain. Personally I was never a big fan of waist finders. Just not a naturally comfortable motion. You can't see if people have their eyes closed, and slow. Furthermore I once dated a girl who was 5 feet tall and she eventually became a big time photographer. Imagine a midget like that with a waist level finder photographing regular people. All chins and nostrils.