Canon AE-1 Manual page 7

Canon Speedlite 155A, the World's First AE Computer Flash Benefiting with the CAT
system used in the professional F-1 model, a new automatic flash system was refined from the
earlier technology used, in which a dedicated flash unit, like the Speedlite 155A is used with
the AE-1, flash photography can be performed with the aperture ring set at the "A" mark for
automatic exposure. When the pilot lamp lights to indicate the proper charging level has been
reached, the shutter speed is automatically set (1/60 sec) and the aperture automatically
determined. After the flash, the camera returns to its original AE setting.
Data Imprinting Mechanism The film back of the AE-1 is a removable part. The Data Back
A, an optional accessory when attached in place of the AE-1's normal back cover, can directly
imprint the date and other information on the negative or slide film at the very moment the
picture is taken. This information is imprinted in the lower right hand corner of the picture
and is most convenient for keeping track of the dates of your photographs or classifying them
in general. However, there was a little mistake made when the design was adopted, nothing
relative to mechanical or electronic flaws - but an oversight which Canon didn't expect that
the databack will be so 'lasting' - the input numerals for the 'year' on the first control wheel
was provided until the year of 1987 only.
However, if compared with the Databack produced by competing manufacturers like Nikon's
MF-12 for the FE, where the LCD version has digits that lasts until the year 2019, the Canon
has some advantages by way of its Roman numerals from I to X, some used it to solve the
problem, of which current years could be indicated by the Roman numeral for the second
digit. The second wheel can be used for months, but also has numbers from 1 up to 31 as well
as letters from A to G. The third wheel has numbers from 0 to 31. As with the other earlier
databacks, you need to plug a short cable which came from the left-hand side of the Data
Back A into the PC terminal socket on the AE-1 camera for proper operation. Well, if you
wish to use the Data Back A and a non-hot shoe flash at the same time, you must plug the PC
cord from the flash into the PC socket on the Data Back A.
There is no doubt that AE-1 has helped Canon shoot to the top as a major
35mm SLR camera manufacturer, with some original ideas such as
automatic film advance devices using a power winder, a convenient and
economical accessory in photography. The Power Winder A, extremely
easy to attach, enables the AE-1 to photograph continuously at up to 2
frames per second. This feature is enhanced by the fact that actual
handling of the AE-1 is very much the same with or without this
accessory attached.