Originally posted by senator I believe the Electro Spotmatic was Japan domestic market and sold as the E.S in other markets.
Alan:
First, welcome to the forum!
The Electro Spotmatic was made for the Japanese home market only. I have seen dates of late 1971 to 1972 for manufacture whereas the ES was produced from the end of 1972 to 1973.
The Electro Spotmatic is one of the more "uncommon" Pentax cameras, and technically it was the forerunner (some say production prototype) of the Spotmatic ES. It was produced in small numbers.
The very early Electro-Spotmatics were prone to circuit board failures. Consequently, it is hard to find and Electro-Spotmatic that works in Auto mode. This was fixed relatively quickly and most of the ES's that benefited from this revision have the revised design and still work. This seems to have occurred in the 1972 timeframe.
Either way, the Pentax Electro Spotmatic was the first SLR camera with TTL aperture-priority.
This is a good read:
Asahi Pentax and Pentax SLR 35mm ... - Google Book Search
Hope this helps! We'd love to see pictures. I've personally been looking for an Electro Spotmatic in working condition for a long time. If you are selling, please let me know. Thanks.
woof!