We see your Contrast and Phase Detection focusing and now show you what Polaroid had for many years: Sonar focusing. It worked similarly to echolocation does for bats and dolphins. The camera, like this Polaroid SX-70 Sonar One Step, waiting until the user triggered the autofocus system. Then the camera sent out a sonar beam and focused on the first thing that it hit. This was a massive improvement over the manual focusing system that the previous cameras had. Sonar focusing was also ignorant of low light situations, backlighting, etc. As long as nothing was obstructing the distance between you and your subject, then it would focus on said subject.
While it sounds incredible, the Sonar focusing system had its drawbacks. For example, if you wanted to photograph your subject who was behind glass, you couldn’t because the camera would focus on the glass. Instead, you’d need your subject to pancake their face against the glass–which we’re sure makes for the most attractive Polaroid pictures.
After the jump, you’ll find a vintage Polaroid commercial that we found showing off how Sonar autofocus works. Check it out.