Somewhere around 1980, I did what I called my “Ultimate Film Test.” Actually it was more than film. I took about 8 or 10 camera and lens combinations, in different formats and bought a dozen or so rolls each of a half a dozen different types of film. I sat up a little still life in my backyard consisting of some flowers, a lawn chair, bird bath and so forth. I then photographed the same scene with every possible exposure and film combination with each camera.
The next step was to make identical 8x10 prints from every exposure, carefully labeling each print as to the camera, lens, film type, and exposure. By sorting the prints in different ways, I could easily see what difference changing the exposure made, the differences in film types, and the differences in cameras and formats.
By using this extensive testing method, I no longer had to rely on other people’s untested opinions, or hearsay. Since at the time I was working with a lot with professional photographers, I could easily bring out clearly documented photographs to show results from the film or camera in question. Very few photographers have ever gone to the trouble and expense to test their equipment and film choices in any significant way.
I began repeating this test about every ten years as film and technology changed. It was then possible to clearly show what changes, usually improvements, had taken places with film emulsions, lenses, etc. by comparing older prints with the newer ones.
One of the biggest variables was the processing, but since I owned a photo lab, this was a constant. Though on other occasions I would use identically exposed rolls of film to test processing techniques.
Now in the digital age, it is even more important to test our equipment and techniques. Film, of course, is no longer a factor, but digital technology is changing all the time. The only way to know for sure if a 12-meg camera that costs $1500, set to ISO 1600, will give better results than a 7-meg camera that costs $500 set at ISO 100, is to test them side by side with the same subject and then make identical prints. Instead of film changes we now have a choice of RAW, TIFF, the various versions of JPEG, and so forth. Which works best, and how much difference is there? If we haven’t tested them and can show documented results, we don’t really know. Plus it might be different next year.
These principles are true in many other areas as well; except in some fields the testing can be very difficult or the results often hard to interpret.
I am also a musician. Testing various types of strings on different guitars, using different amplifiers, cords, picks, and so forth, and actually recording each and carefully analyzing the results is certainly possible, but probably beyond what most musicians are willing to do. Instead we find something we like and stick with it, or we are constantly trying all sorts of variations and never knowing what changed the results.
Most businesses follow this latter model. We either stick with what works, or just keep trying things until, hopefully, we find something that works.