The “A” Series Cameras

“A” Series Cameras and their Introduction Dates

The “A” Series began in 1976 with the AE-1 and continued until 1982 with the AL-1 which was the last in the series. These were electronically operated cameras and required a battery not only for the light meter but to control the shutter as well. Without the battery they will not function at all.

A Few Auto Exposure Terms

Starting with the AE-1 Canon started down the road to fully automatic cameras. But that was a slow evolution in features through many models of camera. This is as good a point as any to look at some of the terms and processes that come up when discussing this evolving technology.

TTL  (Through the Lens) Metering

At first cameras had no means of measuring light. That was done by guessing and experience and then by light meters. When I started taking pictures in the 1950’s I had a light meter which I carried with me. Then cameras came out with a light meter attached to them. And finally the light meter was built into the camera body. The Canon rangefinder Model 7 had such a light meter. So did the Canonflex RM. But those light meters could not see what the lens saw. They measured light coming from the general direction the camera was pointing. In most cases this was enough but in some it was not.

In April of 1965 Canon introduced the Pellix camera in which the light meter was actually inside the camera measuring the light that arrived through the lens. This was the the beginning of what was to become the standard across the industry: true Through the Lens (TTL) Metering.

On early cameras the shutter and/or aperture were set by the operator. When light meters were first mounted on cameras they were still not part of the work flow. They measured the light but they did not communicate with the camera. The photographer still set the shutter speed and aperture based on the light reading. Even with the first TTL light meters, the exposure was still set manually. It was with the AE-1 that Canon actually had the camera take part in setting the exposure.

Aperture Priority (Av)

Aperture Priority is an exposure method employed on modern cameras. In this mode of exposure setting, the lens Aperture is set by the photographer and then the shutter speed is adjusted automatically by the camera to obtain correct exposure.

On Canon cameras this setting is indicated by “Av” (an abbreviation for Aperture Value) on the selector dial. This allows the photographer to control his depth of field himself and not leave it to the camera.

Shutter Priority (Tv)

With Shutter Priority the shutter speed is set by the photographer and the Aperture is adjusted for correct exposure. This setting is indicated by Tv (short for Time Value) on the selector dial.

This would be used, say, in sports photography where the photographer wants to ensure a high shutter speed in fast moving situations. Once set, the camera will not try to change it. It will adjust the incoming light with just the aperture setting.

Program Mode (P)

Program Mode simply means that the camera itself will set the shutter or aperture, or both. On Canon cameras this setting was indicated by the letter P (for Program). It operated in a slightly different manner on various models but it always involved the camera selecting at least one of the variables itself.

Automatic Mode (A)

On Canon cameras this is indicated by a green rectangle on the selector dial. In this mode the camera selects all the variables by itself, automatically, without intervention from the photographer. Most experienced photographers stay away from this mode of operation because they want more control over their pictures. However, for inexperienced customers who want to be able to shoot “snapshots” without having to learn a bunch of controls and theory, this mode is a blessing.

Manual Mode (M)

Manual Mode (M) is indicated by an M on the selector dial and in this mode the operator selects all of the settings himself and any programmed or automatic features are disabled.

PASM Exposure

You may come across the expression “PASM” which is simply an acronym for Program, Aperture Priority (Av on Canon), Shutter Priority (Tv on Canon), and Manual. It means that the camera offers all of these basic modes of exposure.

Center-Weighted Metering

Not only are there different modes of auto exposure, but there are different ways in which the cameras measure the light. The lens takes in a scene but what part of that scene is actually measured? Well, that depends.

If the light is measured towards the center of the scene, with most emphasis taken from the center and less influence taken from the edge of the scene, the method is called center-weighted metering. This was an early method of metering and it is the only mode found on many older cameras.

Spot Metering

Spot metering is exactly what it says: a spot is chosen in the scene and the measurement is taken from it. This allows for very precise measurement of an area so that you can chose what in the scene is recorded in the most detail. This is favoured by people who like to exercise maximum control over the image. It is useful, for instance, in a strongly back lighted image. It allows you to set the exposure for the foreground image which may be in shadow.

Partial Metering

Partial metering is like spot metering except the spot that the camera samples is larger.

Evaluative Metering

Evaluative metering is Canon’s term. Nikon uses “matrix metering” and Pentax and Sony use “multi-segment metering” to describe the same thing. The viewfinder is divided up into zones and measurements are taken for each zone. The recommended exposure is then weighted towards the zone nearest the chosen auto focus point.

Cameras in the Collection

But, enough of the simple explainations. I know they are almost too trivial to mention but hey may help someone figure it all out. I remeber when I didn’t know any of this stuff.

Here are some of the A Series cameras in the Collection: