nr 2 may well be my old one. I made a mount to fil my Leica and was quite pleased with it using Kodachrome.Not having anything better serving the same purpose tp compare with.
The fairly symmetric design makes for nice sunstars while the short focal length ensures good depth of field. I acn still appreciate my old slides from snowdrifts up in the mountains. Being accustomed to keep photoequipment in pockets hence knocking them about, the end bit of the viewfinder unscrewed and disappeared together with the rear viewfinder element. Upon asking Nikon for a replacement I was told I was lucky to get the missing bit since they did not usually keeep such stuff. The ussual way of fixing stuff so it would not fall off in the past before cyano acrylate , was by using Araldite epoxy glue which I probably did.
p.