Nikon Series E 50mm f1.8 Filter Type_Close-Up but this original Kodak measuring

but this original Kodak measuring

This is an original Asahi close-up diopter for any lens with a 49mm filter thread- doesn't have to be an Asahi

but has a slight vertical misalignment

Viewfinder image is dim- the mirror has some corrosion- but the groundglass is intact

Nikon Series E 50mm f1.8 Filter Type_Close-Up but this original Kodak measuringThe Nikon Series E 50mm f1. 8 lens is a compact almost pancake lens (french toast lens?) with a fast f1. 8 aperture. It is compatible with film and digital Nikon F mount cameras (though function will vary). This one is in very good condition, with clean glass and minor cosmetic wear.