Interesting! I've seen advertising for pinholes to put on cameras but never have seen any results. Did you calculate the f/stop of your aperture or take a lucky guess?
I use a constant of 1,56 in my calcs , O,3 mm aperture to 67mm F.L., which is pretty close to the focal lenght of the "Hasselpin", i.e. 73mm.
Results seems nice to me.
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