It's not a serial number, actually, but a combination of date, an identifier relating to the generation of the technology inside (the first letter after the digits, at least on SD cards, is called a "Technology Code"), and some other things that I don't know how to decode. I noticed the Ultra II CF card I have has five digits in the number - no idea how that works out.
I'm glad my quick and dirty pictures worked. They were manual focus and handheld so that I could do a quick bit of focussing by moving the camera in and out. For the two close-up shots of the card, they're shot at the focus limit of my EF 24-70mm f/2.8L as I don't have a proper EF macro lens. They're all really done with slightly too small an aperture (f/16 would have been better than f/11).
All that said, for a quick bit of macro photography with flash (580EX, StoFen Omnibounce, bounced into a white ceiling), I learnt a lot, not least that, if I do eventually buy a macro lens, a focussing rail is a useful gadget to have. If you look carefully, you can tell where I focussed (on the . of 1.0 for the face, and on the text on the reverse.
Given the choice, I would have grabbed the family Ixus 700 (Powershot SD500) that we have here for these shots, but someone else has it at the moment.
What gets me is that on the fake card, the font for GB is completely wrong, and the 1.0GB goes far too far across the face of the card. The label doesn't neatly fit the recess on the front of the card, and - though it could be your white balance - the colours look wrong, especially the red, which isn't a brick red. The paler blue is more of a sky blue shade than cyan, and the edge between the paler blue and the darker blue is sharp on the genuine card.
David
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