[ricardobeat]

The first rangefinder, micking this process mechanically, was invented in 1769. You’re essentially arguing for Lidar / sensor fusion.

Do you have any sources for this being a significant factor in human depth estimation? “Infinity” focus starts at 6 meters, yet we’re able to estimate much larger distances with great accuracy.

[adolph]

I looked up the history of the rangefinder and the work of Watt in the 1770s is kind of obscure. For one, he called it a “micrometer” [0] even though he also created something like what is called a micrometer today, only he called it an “end measuring machine.” Additional confusion comes from “telemeter” as an early term for a rangefinder. Only Watt was also there at the beginning of what we now call telemetry: “additions to his steam engines for monitoring from a (near) distance such as the mercury pressure gauge and the fly-ball governor.” [2]

Watt's micrometer, designed between 1770 and 1771, was what we would now call a 'rangefinder'. It was used for measuring distances, and was essential for his canal surveying work.

Adapted from a telescope, with adjustable cross-hairs in the eye-piece, it was particularly useful for measuring distances between hills or across water.

0. https://digital.nls.uk/scientists/biographies/james-watt/dis...

1. https://collection.sciencemuseumgroup.org.uk/objects/co59281...

2. https://en.wikipedia.org/wiki/Telemetry