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The Canon AT-1 is a 35mmFD-mountsingle-lens reflexcamera manufactured by Canon of Japan from December 1977. It was produced purely for export and was never sold in the home Japanese market. It is a version of the popular AE-1 but without the shutter-speed priority auto-exposure mode of that camera. The AT-1 features manual exposure only. This made the camera cheaper, as some consumers did not desire or require autoexposure and did not want to pay for it.