The Argoflex Forty is my favorite brilliant screen twin lens camera and Kentmere 100 is a favorite film.
Unfortunately, the two do not get along well together.
The problem is the very faint frame numbering on the film's backing paper. Even under bright sun the symbols and numerals are barely visible through the ruby window on the camera's back. The result is that it is very easy to roll the film right past the upcoming frame. On my last neighborhood stroll I managed to lose three of the twelve frames on the roll. Add that to normal loss through missed focus and other mishaps and you end up with a frustrating experience and few good shots per roll.
In fact, most paper-backed roll film produced these days has frame numerals with poor contrast. That is of no consequence for users of cameras with automatic frame spacing such as you would find in later twin lens reflex cameras, but it is a serious problem when the photographer is dependent on seeing the frame numbers through a dark red window on older and simpler cameras.
Here is an example of what roll film backing paper used to look like -- it is from a roll of Pan F 50:
Since I still like the quality of Kentmere in regard to grain and tonality I'll continue to use it with my film cameras that have auto frame spacing like the YashicaMat and the Voigtländer Brilliant. However, I'll look for something else to use in my cameras that require viewing the framing numerals through a ruby window.
