Convincing fakes

You've watched it make pictures and music.

Which raises a thought. Doesn't that make fakes easy too?

It does. But there's something to check first.

Fakes didn't just appear

They go back to when photography itself was new.

Let light onto the film twice, or lay two negatives together while printing the photo onto paper. That's how photographs with ghosts in them were made.

But one print took hours — days, to do it well. You needed a darkroom, and years of practice.

What changed is the cost

You pressed Blend them and got a few milliseconds (a millisecond is a thousandth of a second) — or under one.

Hours became the blink of an eye.

So can you spot them?

Let's find out.

These are the pictures from 5.1. For each one, say whether it's a picture the machine learned from or one it made.

Same pictures. Only the size changed

Round one went badly. Round two went better.

They were the same kind of picture. The only difference was size.

Large, you can see the edges. Made ones wobble slightly and bleed colour.

Small, none of that shows. Size erased the clues.

Are the pictures you see every day large or small?

The ones you scroll past are usually small.

You rarely open them up.

And there's a bigger problem

Our machine is only 32 squares by 32. That's why it shows up large.

Real picture-making AI doesn't show up, however large you look.

A few years ago it did. Six fingers, smeared lettering. Ways of catching it spread around.

Then those clues disappeared, one by one. More will.

Odd doesn't mean fake

One picture in the lab looked odd and wasn't made by the machine at all.

Learn only suspicion and you stop believing real things too. That's its own problem.

Catching every fake isn't the goal.

So what do you look at?

If your eyes can't settle it, look at something other than your eyes.

• Who posted it — where did it first appear?

• Where it came from — is there an original?

• Is it anywhere else — do several places say the same thing?

• Does it carry a mark of where it was made — ways of tagging AI-made pictures are starting to appear

It's the checking habit from 4.4. That was words; this is pictures.

That's AI that makes things

Pictures, music, and convincing fakes.

Next comes what AI can't do.