How Leica Measured Shutter Speeds to the Millisecond with the Bare Eye

Alabama-based photographer and engineer Destin Sandin of the YouTube channel SmarterEveryDay lately visited KameraStore in Finland. Sandin, whose movies ship in-depth technical info in an entertaining and comprehensible method, discovered about Kamerastore’s specialised restoration and testing course of, which incorporates utilizing period-appropriate equipment.

Past repairing and testing cameras, Kamerastore provides the world’s solely digicam mechanics coaching program and technician coaching college. It’s house to tools and machines that might excite any images fanatic, particularly one as within the technical elements as Sandin.

Sandin’s newest video goes behind the scenes at Kamerastore, together with a have a look at a really particular Leica testing machine from the Thirties. The machine permits a educated technician, like Ari at Kamerastore, to calibrate an previous Leica curtain-type focal aircraft digicam shutter. The machine depends upon a rolling shutter-like impact that permits a educated technician to calibrate a shutter by eye.

Leica’s first commercially out there 35mm digicam, the Leica 1(A), hit retailer cabinets in 1925. It, and later Leica cameras, had been among the many finest available on the market. Like many later cameras, early Leica fashions included a shutter pace dial on high. This mechanical dial allowed the photographer to pick a shutter pace, like 1/1,000 second, for instance. The shutter pace dial should be exactly calibrated to the precise pace of the shutter.

If the photographer selects the 1/1,000 second shutter pace, meaning the shutter is open and the movie is uncovered to gentle for only one millisecond. Leica engineers wanted to tune its cameras to make sure that the shutter was open for the anticipated length, with excessive precision. That’s the place the particular calibration machine Sandin noticed in Finland is available in.

The machine measures a millisecond mechanically. Accompanying the machine is an authentic Leica restore handbook — in German, after all — that features diagrams displaying exactly what the shutter ought to appear to be by means of the machine at completely different shutter speeds. At varied rotational charges, a correctly-calibrated shutter will produce differently-curved strains.

Not glad to depart such cool know-how behind in Finland, upon his return to the U.S., Sandin recreated the unimaginable machine utilizing a drill, ketchup bottle, and magic marker. Mixed with a phantom high-speed digicam and very shiny Nanolux gentle that doesn’t flicker, Sandin can use the high-speed digicam to view strains on the ketchup bottle because it spins behind the digicam on a drill.

Utilizing an additive animation method, it’s potential to see the curved strains like what was seen utilizing the devoted Leica machine. Whereas a ketchup bottle with marker strains could appear crude, Sandin’s setup is refined. Leica technicians carried out these measurements with a single machine and the bare eye. Kamerastore’s expert technicians nonetheless do.

One other piece of the puzzle is guaranteeing that the machine’s rotation, or ketchup bottle in Sandin’s case, matches up with a normal pace. In any other case, the achieved shutter pace measurements could also be incorrect. The Leica machine makes use of aliasing, very like a report participant, to permit the consumer to dial in a exact benchmark pace. It’s an unimaginable machine.

Picture credit: SmarterEveryDay, Kamerastore