Why can't I scan a banknote?

Q  I wanted to make a jokey birthday card for a friend whose surname is Cash. I decided I would paste his face onto the image of a £10 note and write a silly message underneath.

So, I fired up my image-editing software and scanned a tenner. However, to my surprise the program refused to scan it! I tried twisting and turning it before rescanning but no matter what I did, the application displayed an error that it was “unable to process” the image.

I then tried it with a £20 note and the same thing happened! What on earth is going on here? My scanner works fine otherwise, so why won’t it scan these banknotes? Is what I’m doing against the law or something?
Amanda Hugh

A Though not exactly common knowledge, it is a fact that some image programs, scanners and even colour photocopiers and printers have tools built in that prevent them from reproducing banknotes of all types and denominations.

The reason for this is that enabling reproductions of currency is a legal quagmire, with different laws in place in different parts of the world.

In the UK, for instance, it is legal to reproduce banknotes so long as certain criteria are followed. Though the rules are long and detailed (see the Bank of England’s current guidelines), essentially you are allowed to reproduce a single side of a banknote – so what you were attempting was not actually illegal.

However, the rules are much stricter in other parts of the world and any attempt to reproduce a banknote could be an offence. Indeed, in some territories supplying the technology that allows it may be illegal.

For this reason some hardware and software companies nobble their wares to prevent all attempts at reproducing currencies, though obviously they don’t shout about the existence of this restrictive technology.

For more information on what’s legal and illegal, and where, visit the website of the Central Bank Counterfeit Deterrence Group (of which the UK’s central bank is a member).

However, as we said, what you were attempting isn’t actually against the law – but your image-editing software is playing the over-zealous security guard. Not all programs are this concerned, and some aren’t bothered at all.

We should also say that it might not be the image-editing software at fault here – it could be the scanner’s own driver. But as you gave us no further details about the setup we’d suggest trying a different image-editing tool first. The Gimp is a popular free option.