Contax RTS II Gebrauchsanweisung Seite 16

(Exposure Counter)
The exposure counter advances one number every time the fitm
advance lever is operated, and returns to ,,S" (start) when the
rear cover is opened, regardless of whether or not film is loaded
in the camera. The exposure counter on top of the camera starts
with "S", then goes to "1" followed by even numbers ,,2"
through "36". The odd numbers from ,,3" onward are indicated
by dots etched between the even numbers. The numbers ,,12",
"20", "24" and "36" are in orange since they indicate the
number of exposures given on standard 35-mm film cassettes.
. Memo Holder_:,
Use the memo holder to remind yourself of what type of film is
loaded in your camera by slipping the end of the film carton into
it, or even use it to hold the exposure data for the shots you
have taken.
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