You can date Kodak film stock by the code marks exposed on the edge of most motion picture films made since 1916. The date codes repeat every twenty years.
Remember that the date code refers to when the film was slit and perforated. In amateur use a year or two may have elapsed between manufacturing, distribution, photography and processing....also, some film is aged to stabilize its characteristics before offered for sale.
Further points of identification: 16mm has been manufactured only since 1923, regular 8 film since 1932, super 8 made its appearance in 1965. As to film types, black and white reversal was introduced in 1923. Kodachrome in 1935, Kodachrome Commercial in 1947, and Kodachrome II in 1961. Kodachrome Commercial 5268 was replaced by Ektachrome Commercial 7255 in 1958, which in turn was superceded by Ektachrome Commercial 7252 in 1970.
Following is a chart of edge identification for some commonly used film types, and the translation:
EKTACHROME C SAFETY FILM: Ektachrome Commercial 7255
EASTMAN ECO SAFETY FILM: Ektachrome Commercial 7252
EKTACHROME SAFTEY FILM: Ektachrome ER 7257
EKTACHROME B SAFETY FILM: Ektachrome ERB 7258
KODAK SAFETY FILM (color stock) Ektachrome MS 7256
KODACHROME SAFETY FILM: Kodachrome Daylight, or Kodachrome Duplicating Film
(with edge numbers): usually Kodachrome Commercial 5268
KODACHROME A SAFETY FILM: Kodachrome Type A
KODACHROME II SAFETY FILM: Kodachrome II
KODACHROME II A SAFETY FILM: Kodachrome II Type A
EKTACHROME EF SAFETY FILM: Ektachrome EF 7241
EKTACHROME EFB SAFETY FILM: Ektachrome EFB 7242
EASTMAN REV SAFETY FILM: "Kodachrome" print stock 5269
EASTMAN REV II SAFETY FILM: "Kodachrome" print stock 7387
KODAK N SAFETY FILM: Black & white negative
KODAK R SAFETY FILM: Black & white reversal
KODAK SAFETY POSITIVE: Black & white release positive stock
EASTMAN SAFETY FILM: Might be anything of recent manufacture including
EFB 7242, 7387, 7389, 7390. Must be identified by examination.
EKTACHROME REV PRINT SAFETY FILM: Ektachrome print stock 7386
EKTACHROME R PRINT SAFETY FILM: Ektachrome print stock 7388
