This Lens Was Way Ahead of Its Time

We take ridiculously powerful autofocus that can lock onto something like a subject's eye and track it through a challenging environment for granted nowadays, and we sometimes forget that there was a time when autofocus did not even exist. However, in the late 1970s, autofocus began to appear, and even though Canon's lens mount at the time did not support it, they found a way to put it in a lens anyway. This neat video review takes a look at that lens. 

Coming to you from Christopher Frost, this great video review takes a look at the Canon FD 35-70mm f/4 AF lens. Though it seems like a very pedestrian lens by today's standards, it is important to remember that this lens arrived in 1979, nearly a decade before the EF mount. As such, all autofocus capabilities had to be built into the lens itself, thus its strange, boxy design. To accomplish autofocus, the lens used "Solid State Triangulation," which used the two visible fixed mirrors to compute subject distance and adjust the motor accordingly. Of course, it became pretty archaic even just a decade later, but when you consider the fact that just a few years before this, autofocus and auto-exposure were exceedingly rare or nonexistent, it becomes easier to see just how revolutionary this time period was. Check out the video above to see how the lens works.