[tagoregrtst]

126? 110 (other comment)? By that token betamax was a successful format in 1975 before VHS launched.

35mm was the top selling film since the 1960s until digital took over.

You went to any drugstore and you found 35mm. Maybe a box or two of APS. Maybe some medium format. But you could find 35mm in every drugstore, gas station, street vendor in a tourist trap without fail.

Professionals used 35mm because it was snaller than MF and for many things good enough. Otherwise it was considered consumer grade.