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Film
I'm using 5" aerial film for this camera
I found that the wheel that measures how much film is being wound through the camera adds too much friction, especially with the thin based aerial film, so I place a piece of cardboard under the wheel, so it doesn't touch the film track. It's easily removed without having to modify the antique in any way
Exposure
Al Vista cameras had a few different Drive mechanisms that controlled the movement on the lense. The most common is the fan regulated gearbox
This photo shows the gearbox of a 5b camera, with a fan sticking out of the bottom
The camera usually came with 5 fans numbered 1-5. The camera pictured is a 5-d,
and had the fan on top of the camera. The smallest fan would give the fastest exposure
The cameras had a exposure table on the back door
I'm working on getting a 5-b camera ready to shoot and made up a spec sheet as follows
Al Vista 5-B
5” lense
12 inch by approx 4.5” usable image on 5” wide film
lense opening .425” = F11.76
waterhouse stop opening
serial # 7786
no fan 1/16 sec
#1 three second fan 1/8
#2 six second fan 1/4
#3 eight second fan 1/3
#4 ten second fan 5/12
#5 twelve second fan 1/2
maximum F stop =F 11.76
5 divided by .425 =11.76
5 divided by .31=16.12 F16
5 divided by .28=17.85 F16 1/2 or f 18
5 divided by .24=20.8 F22
5 divided by .31=16.12 F16
5 divided by .15=33 F32
5 divided by .12=41.6 F45
5 divided by .09=55.5 F55 (451/2)
Although there were a few late model cameras that had diaphram apertures, most al vistas had waterhouse stops, including the 5b. I needed to measure the stops and figure out the f stops to use them. The later numbers are are rounded off for easier use. These waterhouse stops were homemade by a earlier user, and won't correspond to the factory stops.