Hi Peter
Photographing hallmarks is always a tricky matter, so I made a device to try to get better photos.
It does not really improve the sharpness of the image, but it allows me to go closer to the marks without shading them with the black plastic part around the lens.
I have tested this device by photographing the maker mark of the ink stand, which is somewhat difficult to reach.
I have obtained this picture, where it is well seen that the second letter is not a B, but an A or, at most, an R.
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What do you think about it?
Best
Amena