The AE-1

Keeping costs down meant simplifying the design, less expensive materials and simpler assembly methods to control labor costs. One of the methods the Canon design team  adopted to simplify construction and keep weight down  was to incorporate plastic into the construction of the camera. Plastic is cheap and it can be molded into complex shapes easily. The bottom plate of the new camera was the traditional stamped brass and the body frame was molded and machined from a light metal alloy. However, the top deck of the camera was a dense plastic, although most people never knew that. It was injection molded was then plated with layers of a metal compound and then  finished in the same chrome treatment that the brass bottom received. The top deck was a complex shape that could be made very cheaply and yet retain the classic finish. The brass and the plastic parts were indistinguishable.

Inside the camera use was made of plastic gears and other parts that were easy to make and which made the camera lighter. When first introduced there was much criticism of the use of plastic parts but the 50 years since the introduction of the AE-1 has proven the design to be sound. There are lots of AE-1’s around that still work flawlessly. Those that did fail did not do so because of the use of plastic.

At the time the design of the AE-1 was being worked out Canon’s business division was working with Texas Instruments to develop business calculators using microprocessors and so the company engineers were familiar with integrated circuits which were just coming into wide spread use. They went ahead with a camera design using a microprocessor to control many of its features. The AE-1 was the first camera to incorporate an integrated circuit into the camera’s operation. By doing this Canon says that they were able to eliminate about 300 mechanical parts from the camera making it cheaper and easier to assemble.

All of the camera timing functions were controlled electrically through the microprocessor. It was mounted on a flexible printed circuit which was wrapped over the top of the pentaprism under the top cover. This small

computer controlled the shutter, horizontally travelling fabric curtains, through the use of solenoids which eliminated any mechanical connection between the shutter button and the shutter mechanism.  For this reason the AE-1 will not work without a battery.

Since timing was now electronic it was possible to do away with the clock work mechanisms that controlled longer shutter speeds and the self-timer meaning that the camera could be made smaller. In the new camera the only clockwork mechanism was the Mirror Damper used to soften the mirror movement.

Remove the bottom and you find this. Left of center in the plastic cover is one of the three selinoids that control the shutter. Another is visible to the left of center attached to the red wire.

Years before the introduction of the AE-1, when Canon came out with the FD lens mount and lenses, they had anticipated fully automatic exposure and FD lenses had an automatic setting indicated, on early lenses, by a green “o” on the Preset Aperture Ring, and on later versions by a green “A”. They offered fully automatic exposure on the F-1 but that was an expensive professional camera. Other manufacturers offered the same in their high end cameras.

The AE-1 was to be aimed at entry level users but Canon wanted a camera with advanced features that was still economically priced. They already had lenses designed for automatic operation, the lens mount was capable of it, and so it was decided that the AE-1 would have fully automatic exposure. In fact, it was intended that the camera be fully automatic with manual operation offered as a backup. It was designed to be a “point and shoot” camera with the option of using it manually or adding lenses and accessories for a more advanced experience.

Introduction of the AE-1

The introduction of the AE-1, AE being the initials of “Automatic Exposure”, in April of 1976 was timed to coincide with the 1976 Olympics in Montreal. Canon had developed an advertising relationship with sporting events and had become the official camera of several events including the Olympics. They even created commemorative cameras such as the F-1 for the Montreal Olympics in 1976, the Lake Placid Olympics in 1980 and the Los Angeles Olympics in 1984.

Canon did not create a commemorative camera for the AE-1 but the Olympics features heavily in its advertising. And there was a commemorative lens cap , shown on the left, which appeared on the AE-1.

Canon began an extensive international advertising campaign with a heavy

emphasis on sports photography and featuring endorsements from prominent sports celebrities. This, combined with the advanced features and amazingly low price, propelled the AE-1 to sales of over 5 million units during its production run from 1976 till 1984. It was the first SLR to achieve sales of one million cameras and eventually it was the best selling SLR of all time.

Features of the AE-1

The AE-1 was offered with either the FD 50mm f/1.4 S.S.C. of the FD 50mm f/1.8 S.C. lenses. Although intended as a fully automatic entry level camera the AE-1 had sophisticated features and abilities and would accept all of Canon’s F Series lenses. When the AE-1 was introduced the FDn lenses were still three years in the future but it worked flawlessly with them. Of course, having no mirror lockup facility, lenses that extended back into the mirror box, such as the FL 19mm f/3.5 cannot mount n the AE-1. FL lenses could also mount on the AE-1 but to use the built in light meter readings had to be taken with the camera stopped down and of course the aperture had to be set by hand.

The shutter was two horizontally travelling cloth curtains timed and controlled electrically. Shutter speeds were 2 seconds to 1/1000^th of a second. X and B settings were included and an electronic self timer was included with flashing LED to indicate operation.

Flash sync was via a hit shoe on top of the prism housing or the PC Socket on the front of the camera. More about that below.

The viewfinder screen has a microprism focusing area in the center with a split image for accurate focus. Along the right edge was an f/stop scale and the meter needle indicate the f/stop for the shutter speed chosen. The shutter speed was not indicated in the viewfinder. A flashing red M indicated the camera was set in automatic mode and a flashing red LED indicated that there was not enough light.

The light metering system used an SPC (Silicon Photo Cell) mounted just above the eyepiece and sensitivity was averaged over the viewfinder area with emphasis on the center portion. Canon called this Center Weighted Averaging.

The lens could be stopped down to check depth of field and also to allow for stop down metering.

Film speeds that could be selected were from ISO 25 to 3200.

With the AE-1 the venerable mercury cell was done away with and the camera used a 6 volt alkaline battery such as the 4LR44. Presumably a voltage regulating circuit was employed to compensate for declining voltage as the battery aged.

Mirror lockup was omitted in the AE-1 as was the ability to make double exposures.