For a number of years I managed a department that produced sets of test film. These were made in a studio setting using electronic flash.
A model is decorated with calibrated color and gray patches. Prevalent film types were purchased in mass and carefully stored. Generally each film type was exposed as a set that consisted of over, under and normal exposures. The finished negatives and slides along with target prints were used world-wide to calibrate automated printing devices. The exposures and the subsequent processing was maintained to better than 1/6 f-stop tolerances.
Keeping the color temperature of the exposing strobe light constant is daunting. The electric supply main for the strobes was wired 200% oversize. The breaker box was isolated from the other electric loading in the building. The electric power to the strobes was fed to a constant voltage regulator.
Periodically during the day, the exposing light was checked via light meter and color meter. The factors to be considered are: voltage, temperature of the strobe power supply and temperature of the flash tubes. Few flash units and voltage regulators are up to the task. Additionally the ambient light and wall décor must be specified and maintained over the years. Instruments to measure the light, the film and the prints must be constantly checked.
Again, maintaining 1/6 f-stop (0.05 density for all three primary colors) is daunting.