第四版1969 - 1979，黑色镜筒上没有“50”字样，没有对焦锁和把手。

Fourth version 1969-1979 Black lens with no "50" on barrel, no focusing lock or lever.

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另外，使用支持e - TTL II的相机时，闪光的测光不再与当前对焦点联动-这降低了锁焦和重新构图时发生曝光错误的机会。

Furthermore, with E-TTL II cameras, flash metering is no longer linked to the AF point you're using - this reduces exposure errors if you prefer to lock focus and re-compose.

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