Once we have our crystal, we put it in front of a narrow beam of X-rays. Because the crystal is made up of regular repeats of the protein, it scatters the radiation into thousands of rays. The direction of these rays tells us about the way in which the protein is packed inside the crystal. The brightness tells us about the structure of each protein molecule. This picture shows what our experiments look like.

Sometimes, to stop the X-rays damaging the crystals, we cool them to temperatures of around -173 degrees centigrade !

Here is how the crystal is moved during the experiment.

And

Here is how the detector sees the beams of X-rays.