Quote:
one vertical scale to the left at 9 divisions distance from the center one : how many degrees/grads ?
a parallel hair to the horizontal one at 9 graduations : how many degrees/grads ?
a scale close to the center vertical line with many smaller divisions : how many degrees/grads ?
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In most periscopes you will see (NOT in the US ones, BTW) the field of view has a vertical and an horizontal scale, where the vertical one is divided in milliradians (10 milliadians = Aprox 5.75 degrees) and the horizontal in degrees. Such is the case in the periscope view from Flore, as you can see that the vertical and horizontal divisions do NOT have the same size.
Now, in the typichal pictures from german WW2 films you can see, as well as in this one you have posted that is apparently from WW2 french defence ministry, the divisions are more peculiar. You can see that sometimes there are 5 and sometimes there are 4 divisions between the "10" mark and the central line of the crosshair. Why? We had a discussion long ago about that (Look
HERE), but so far I think that the best explanation possible is that the reticle combines BOTH milliradians and degrees, i.e. where you have less divisions you are actually seeing degrees, and where you have more divisions you are seeing milliradians. This would allow to have both degrees and milliradians in both vertical and horizontal scales.
