How do u convert between ASA, DIN, and ISO? I have a classic camera ca.1950s with only DIN and ASA, and they dont seem to be equivalent to ISO (i believe they have since changed the formulas and they are now equivalent). DIN goes from 5 to 650, doubling with every increment. ASA goes from 12 to 33, adding 3 with every increment. Id like to know what these values are in today's ISO terms. Thanks!