35mm, medium format and when possible, much larger formats like 8 x 10 and 11 x 14.
The loss of Eastman as a film producer put an end to some of the work I once did, like using BIG film measured in feet. For example, 8 and 16 inches wide by 20 feet in length. I once carried around a five inch aerial camera for "snapshots."
Kodak put an end to photography for the most part. At one time, they stocked three hundred or more different films and glass plates as well as more than 50 papers in 30+ different weights and surfaces. Not to mention tens of thousands of photographic sundries.
Kodak went so far as to introduce new films for cameras that were discontinured twenty years hense. The customer was king as far as Eastman was concerned.
I also shoot some stereo photography and occasionally dabble with old processes like Vectographs and other obsolete techniques and processes.
I was a working pro for many years as well as a darkroom manager and printer. I can still make a fine quality black and white print, I'll bet.
Times have certainly changed.
My preferences for equipment include the Leica M system, Hasselblad, Linhoff, 8 x 10 Kodak Master View Cameras and EK Banquet Cameras. Stereo Realist for 3D.
Now, I am looking at one of these for 14 MP 5K digital stills:
RED Digital Cinema Cameras, Lenses and Accessories
So yes indeed . . . I know just a little more than just a little about photography.