Speed of 120 Autographic film

The instruction manual for my No.2 Folding Brownie (circa 1920) gives

recommended exposures using the Uniform Standard aperture and the cameras two speeds of 25 or 50.

Are these speeds in fact 1/25 and 1/50? What is the speed of 120 Aoutographic film for that period?

Thanks in advance.

<p>Yes, 25 and 50 are 1/25 and 1/50 of a second. You can find a mapping between Uniform Standard apertures and standard f-stops at <a href="http://user.itl.net/~kypfer/folders.htm">

http://user.itl.net/~kypfer/folders.htm</a>.</p>

<p>

From the exposures Kodak was recommending in 1920, I'd reckon that the film (Autographic or Non-Curling) was ASA 12. By the 1940's, Verichrome (<i>not</i> Verichrome-Pan, the original Orthochomatic version) was the same speed as Panatomic-X, thus around ASA 32-50. This agrees with exposures in period Kodak instruction books.</p>

<p>I have a No. 2 Folding Brownie Model C, and testing has revealed that the lens is quite soft unless you stop it down to one of the smallest two apertures. Stop it down with ASA 100-125 film.</p>