Silly question on manual film speed setting (Did I get it right?)

[Rurouni]

Let's say I have a camera that can take film from 25-3200, and its supposed to be able to adjust in 1/3rd of a stop at a time.

The dial is something like:

25 - - 50 - - 100 - - 200 - - 400 - - -1000 - 1600 - - 3200 (where the '-' are the unmarked speeds since u can't print everything on the dial and the bold numbers are the printed speeds)

Haven't used an all manual cam for a long time, so did I fill in the film speeds right? I.e:

25 (32) (40) 50 (64) (80) 100 (125) (160) 200 (250) (320) 400 (500) (640) (800) 1000 (1250) 1600 (2000) (2500) 3200 ?

I think I have really become out of touch with film and manual cams

[Zerstorer]

Just look at the number of division in between. If there are 2 then it should be a 1/3stop increment.

So just multiply the marked iso by 2^1/3 or 2/3 accordingly for each unmarked iso.

Your calculations are correct.

[sabrewolf]

I guess you are rite but do you really need to know the actual speed number, most likely you need to know all the typical film speed, which are the ones that is printed on the shutter dial except 1000 which should have been 800 but for some reason Voigtlander decided not to use.

[ricohflex]

typical depends on the film you use
eg. kodak plux X pan is asa 125
their GPF (do they still make it?) was asa 160

guess Ilford got a b+w film that is asa 32

[student]

Originally Posted by ricohflex guess Ilford got a b+w film that is asa 32

I am not aware that Ilford has a film with ASA 32. The slowest speed is PanF 50. But I often rate that at ASA25.