Hi skip, just wanted to point out that SCAF stands for "Ship Centered, Accuracy Fix"....a mod I made years ago to fix the inaccurate mast height measurements found in the Recognition Manual. Those measurements are directly used when taking a Stadimeter reading during game play. Some heights are off by several meters, which will return Range findings off by several 100 meters!
Although....... I've revised many height measurements to be more accurate (then SCAF) with the mod.....
Optical Targeting Correction.
One thing I didn't count on during my SCAF making days was the fact that most of the subs don't have the Stadimeter/Periscope as the center point of measurement. This means my corrections with SCAF are good for one particular view bearing......but will be slightly off in another. OTC corrects this off center position, giving reasonably accurate measurements in all view bearings. Correcting not only for the Stadimeter, but also the periscope Telemeter Divisions too (those are the hash marks on the periscope lens).
You mention the length measurements, yet OTC is the only mod that provides length measurements in the Recognition Manual. It's with the accurate Telemeter Divisions scaled to the correct optical view that will provide a good estimate of AoB using only the periscope (as it would in real life).
My apologies for bringing this up in someone else's thread regarding an "Is-Was". However, back in 2007 I also made a similar devise and called it an
AoB Calculator (I never knew what an Is-Was was until after making my calculator). I only bring it up because you asked for "other practical uses", which you may find if you download and read "
High Realism Tutorial".