If you're a film photographer your fridge (or fridges) probably looks something like this ...
I've got over 2o different film stocks in my bar fridge (there are a few on another shelf), plus some Kodak Portra 800 & Ektar in the kitchen fridge and 5 rolls of Kodak Aerochrome in the freezer - let's call it a total of 25 to choose from.
Which is amazing, because I seem to have a film stock to suit every possible shooting scenario - daylight or tungsten light, warm colour film, cooler colour film, slow (25 ISO) or fast (there's a roll of Kodak T-Max 3200 somewhere), 'regular' B&W, fine grain B&W, even B&W infrared, instant film, etc, etc, etc.
But it is causing a problem - I'm not shooting anything consistently which means my results are all over the place. I just don't have enough experience on any of these to know what to expect under a given lighting/subject/camera/lens combination.
Don't get me wrong, I've got a reasonable idea of what the results will be, but I'm not confident with a specific stock to know exactly what to expect.
While I believe that part of the joy of shooting film comes from the uncertainty of film, I'm a getting a little to much uncertainty.
Which brings me to the beginning of the "HP5 experiment" - I have purchased 10 rolls of HP5 in 35mm and another 10 rolls in 120 and I plan to shoot nothing else until all 20 are exposed, developed and scanned.
While I'll shoot most at box speed (400 ISO), also I plan to:
try overexposing by a little bit - say 320 and 250 - with regular development times
pushing to 800, 1,600, maybe 3,200 and develop accordingly
And the plan, when I get to 20 rolls, is to pick a colour film stock (I'm thinking Kodak Vision 3) and repeat the process.
Check back from time to time for the results!