Recently I purchased a German fold-able camera which was produced in about early 1930s. Got it from camera collector who told me he never tried that camera.
To my surprise when I got this camera home, I've discovered that there's still film inside of it (I can see backing paper of the film through the window that shows frame #4).
Now I absolutely want to finish the roll and develop it. The problem is I have no idea what film is inside and how old it is.
The strategies I'm thinking about:
Just bracket all 4 remaining exposures (the camera is 6x9, so there's 8 in total). But here's a thing: potentially the film could be about 90 years old (probably not but theoretically), using the "add one stop per decade" it makes about 9 stops. I googled that films from those years are typically 25-100 ISO range. So in the best case scenario I'll be dealing with film of about 0.12 ISO. But at the same time the film could be a couple decades old only. This will give me theoretical range of 7 stops, which I can't properly cover with only 4 exposures left.
Wind the film in camera. Take it out. Rewind it back to intake spool in darkroom. Take a look at backing paper and try to figure out what ISO the film is and when it was produced (not even sure if I will be able to get any info from the backing paper). Then load again, wind to frame #4 and shoot having at least some info about it. The con is: I'm pretty afraid to ruin the film during the rewind process.
What's your best strategy in this situation? How would you develop it?