Flying from Whitehorse in the Yukon Territory(Canada) to Norman Wells in the North-West Territories in late summer of 1955, we ran into this massive thunderstorm. Our sturdy DC-3 Dakota was unable to fly over it, so we had to employ the dodge-and-hold-on maneuver, which meant getting a firm grip on anything solid and hanging on while the plane rolled and plunged through the turbulence. Air-sickness was not an option. The photo was shot through the rather grimy perspex window which didn’t really enhance clarity, but it appeared the shutter speed was fairly accurate. Guessing it was probably 1/50 at f 8.0 ,using a 50mm. Biotar lens on an Exakta Varex 35mm. SLR.
The film was Kodachrome ASA10, and the slide was scanned 49 years later at 4000dpi using a Canoscan4000US scanner.
I do try to hold onto memories!