JMC1969
Subscriber
I got this with a bunch of other camera gear and I'm not 100% on it's best use. Came in a small black leather(ish) case. It fits over the viewfinder of the Pentax K1000 I have hear. The piece itself focuses and magnifies as you look through it. So it seems it is some sort of fine focuser that adjusts to your eyes (as in Diopter) . Maybe someone here has more info and/or use for this.
Thank You
Thank You