The Rise of the "E" in SLR Cameras

    "Auto", "Automatic", words beginning with "Auto..." and words ending in "...matic" have long been the stock in trade of the camera manufacturers/marketers (closely followed by the use of "Super"). While we may suffer from "auto" overload from time to time, or feel that automation has gone too far today, without the camera companies' obsession with automating the SLR, we would probably all still be shooting with rangefinders and TLRs (twin lens reflexes), or we would be manually flipping our mirrors back down after each shot, "pre-setting" our apertures, re-cocking our shutters manually, developing our film in the bathr...oh...wait...a lot of us still do that ;-). Anyhow, you get the idea. The beauty of vintage SLRs is just about anyone can find a model (ha, try keeping it to just one ;-)) with the level of automation they want. So let's take a trip back to the time when everything auto was new and exciting and was going to change the world...and we'll end up with lots of camera models with "E" in their names. 

---

  Automatic SLRs For the People

    We have the Asahi Optical Company, later named Pentax, to thank for starting the SLR down its long road to the breathtakingly complex DSLRs of today. And all they wanted to do, in 1952, was make the reflex mirror come back down on its own (or automatically :-)) so that the photographer wasn't stuck with a blacked-out viewfinder after taking a picture. As an aside, in 1949-50 there were a few hundred Duflex SLRs produced by the Gamma Works in Hungary with an instant-return mirror, but they were virtually unknown in the outside world; Asahi Opt. Co. was the first to bring it to the mass market with the Asahiflex IIb. The same held true for the other innovations of the Duflex: automatic aperture and a pentamirror (a pentaprism was used in the prototype) viewfinder that gave an un-reversed, upright image. Other manufacturers would often get the credit for these advances only because they worked in a larger market. And sometimes, innovations occurred nearly simultaneously. Thus began the slippery slope to seemingly non-stop automation by the SLR manufacturers. Please keep in mind this will not be an exhaustive list of all innovations, we'll just hit a few of the more pertinent high points along the way:
​

• 1958 - Asahi Auto Takumar lenses automatically stop down the aperture but require manual re-opening  by a lever on the lens.
• 1958 - Minolta Auto Rokkor lenses also stop down automatically and re-open semi-automatically by winding the film to the next frame.
• 1959 - Nippon Kogaku (Nikon) Auto Nikkor lenses have fully automatic stop-down and re-opening of the aperture immediately following exposure. As do some of Canon's R-mount lenses, but they have a fiddly DOF ring on the lens that complicates matters somewhat.
• 1961-2 - Minolta and Asahi catch up to Nikon with fully automatic aperture opening and closing. Minolta sticks with Auto Rokkors while Asahi now calls their lenses Super Takumars. Hmmm. A sign of things to come, perhaps?

     Next up for the engineers was the task of integrating metering within the camera body and enabling the camera to do so through-the-lens (TTL) at full aperture while coupled to the lens. Up until this point, meters were separate handheld units or clumsily clamped on bits that added bulk and had to be manually coupled to the camera's shutter speed dial. Let's see how the manufacturers got beyond that:

• 1962 - Minolta introduced the SR-7 with a built-in Cds (cadmium disulphide) meter that used a window-mounted cell in the left shoulder of the camera and that was coupled internally to the shutter speed dial so that the meter suggested exposure based on the shutter speed set. Nicely integrated, but not TTL. It still used Auto Rokkors, though ;-).
• 1964 - Pentax brought us the Spotmatic, three years after showing a prototype that had a TTL spot meter. The TTL survived, but the spot meter was changed to an averaging one. You also had to stop down the lens manually for meter readings. Still, the Spotmatic with its Super Takumar lenses was a sales smash.
• 1962 - Wait a minute, we were already up to '64! Sorry, but Tokyo Kogaku (Topcon) didn't co-operate with our tidy timeline of incremental improvements. In late 1963 they introduced the...RE Super aka the Super D...with both TTL metering and at full aperture at that!! And to top it off, RE Auto Topcor lenses! No, no, no...too...much...Super...auto...matic...slipping...away...must...get...control...deep breaths...deep...breaths, ok, ok. Whew! Sorry about that, had a little moment there.

    Alright, where were we? Ah, yes, so where would automation strike next? Well, up till now users still had to set both shutter speed and aperture manually for proper exposure. What could be done about that? Well:

• 1964 - The Topcon Auto 100 combined the TTL metering of the RE Super with shutter-priority auto-exposure, meaning that the once the user selected a shutter speed the camera would automatically select the appropriate aperture setting to reach the exposure determined by the meter. The only catch was that the Auto 100 used a leaf-shutter mounted behind the lens mount while most SLRs used the focal-plane shutter which is capable of higher speeds but more difficult to adapt to auto-exposure. That left an opening for another innovator.
• 1965 - The Konica Auto-Reflex was the first auto-exposure SLR using a focal-plane (directly in front the film surface) shutter. Like the Topcon Auto 100 it used shutter priority automation with a mechanical shutter. However, it lacked  TTL metering. Say it ain't so, Joe!
• 1967 - Zeiss-Ikon introduced their Contarex Electronic, the first SLR with an electronically-controlled focal plane shutter
• 1968 - Konica returned with the Autoreflex T. This time with the whole package, shutter-priority auto-exposure and TTL metering. Yashica did Zeiss-Ikon one better by delivering the TL Electro-X, the first successful electronically-controlled shutter SLR (300,000 sold vs. 3,000 Contarex Electronics). The apocalypse was nearing...
• 1969 - Canon introduced it's first, somewhat quirky, shutter-priority TTL SLR. It had only 4 lens options that attached to a permanently mounted rear group with the focusing unit built in. But the interesting thing about this camera was its model designation, EX EE, which predicted the coming revolution and rise of the letter "E" to heights only previously known by Auto...Super...and...matic. EE stood for Electric Eye, used to designate the shutter-priority setting on the camera. Now Electric Eye had been used by Topcon in the Auto 100's user manual, but this was the first time it had been used (to the best of our knowledge) in the model name of an SLR. It wouldn't be the last. 
• 1971 - Pentax developed the first aperture-priority SLR with an electronically-controlled shutter (the user sets the aperture, the camera sets the corresponding shutter speed) auto-exposure. It called its creation the Electro Spotmatic, setting off the great invasion of electrified SLR shutters and aperture-priority automation.
• 1972 - Nikon responded with its Nikkor/Nikomat EL. Pentax persevered with the newly refined initials-only ES.
• 1972 - The Praktica LLC introduced electronic aperture stopdown control. 
• 1973 - Canon crashed the party with the shutter-priority EF. Pentax proliferated with the ES II.
• 1974 - Minolta unleashed the XE. The adoption of electronically controlled shutters by the main Japanese manufacturers was complete. And that was just the beginning. By 1980, there had been cameras labelled AE-1, ME, EL-W, XG-E, EL-2, FE, and of course, ME Super. 

     Electronics would be the driving force behind the next 40 years of automation and computerization in SLRs. Engineers would use them to advance from shutter and aperture-priority auto-exposure to fully programmed auto-exposure. They would integrate powered film advance and rewind inside SLR bodies, and electronic LED & LCD finder displays. Canon would introduce its EOS (Electro-Optical System) that uses EF (Electro Focus) lenses in 1987. "E" would eventually...power the digital revolution with Super CCDs, Auto ISO & White Balance, and give us camera models such as the Olympus OM-D E-M5 II. The more things change, the more they stay the same ;-).

        Next time...The Shrinking SLRs of the Seventies
​

    References:

       The SLR Saga: From Here to Eternity - Popular Photography Aug. 1994
       Duflex SLR @ www.pentax-slr.com
       Duflex @ camerapedia.com
       Canon EX EE @ User Manual @ www.butkus.org
​       Konica SLRs @ www.buhla.de
       Konica Autoreflex T Manual @ www.butkus.org
       Minolta SLRs & Auto Rokkor Lenses @ www.rokkorfiles.com
       Minolta User Manuals @ www.butkus.org
       Nikon Auto Nikkor Lenses - Nikon F User Manual @ www.butkus.org
       Asahi/Pentax SLRs & Lenses @ www.pentaxforums.com
       Pentax User Manuals @ www.butkus.org 
       Topcon SLRs & Auto Topcor Lenses - User Manuals @ www.butkus.org