Hi, thanks! I’ll consider your suggestions, however, keep in mind that postage stamps or banknotes are very different in shape, size and design across different countries. It was a real challenge for me how to create a universal test that anyone can reproduce on their end.

Those Sandmarc lenses are interesting, but they are also a bit too expensive for me, particularly if I take into account shipping costs, so it’s unlikely that I will ever test them. Also worth noting, each phone model (or generation) uses different lenses and sensors, so technically, those adapters should be matched, as well. You can mix and match lens adapters and phone models/brands with more or less good results, but ideally, lens attachments should match specific phone model(s) for best possible results. And that is additional cost factor to take into account.

Could you do the same with the Sandmarc lens?

youtu.be/BR1TuEEq_fA

But, instead of using a KEYBOARD, why not use something like a small POSTAGE STAMP, printed with clear halftone dots?
Thanks again for the review.