GOI Prototype Lens Set 30cm & 50cm f. Reflex Housing Prototype

1. A partly black painted GOI LENINGRAD 4.5/30cm TAIR-30 tele-lens with serial number 49074755. On the side of the front marked OB 11. The GOI Lens Catalog shows exactly such a lens but describes it with OB-79. Calculated in 1944 and the test chart entering took place in 1950 which matches the serial number of the lens (49 indicates the year, the 4755 is the "serial number“). It comes in its beautiful wooden box with matching serial number marked FOTOOBJEKTIV TAIR. 2. A black paint GOI LENINGRAD 8/50cm tele-lens with serial number 49064739. On the side of the front marked OB245. The GOI Lens Catalog shows exactly such a lens. Maybe it is even this lens as only this lens surfaced so far. Calculated in 1948 and the test chart entering took place in 1949 which matches the serial number of the lens (49 indicates the year, the 4739 is the "serial number“). The GOI construction plant is the prototype plant for Russian optical systems in Leningrad. They produced the prototypes from around 1931 and then sourced the information to real manufacturers, KMZ, GOMZ, etc. which then mass-produced their lenses. But not all of course.