The secret to being a master of disguise? Keep it simple ...

IT’S good news for secret agents. Just simple changes to their appearance can cut the chances of recognition by a third, a study has found.

Researchers asked 26 people to change their faces in a photograph, by altering their hair, make-up, expression, facial hair, glasses or the camera angle they posed with.

Digital trickery or prosthetics were banned from the research. Nevertheless, the chances that the volunteers would be recognised fell by 35 per cent. Even those who were friends or colleagues were less able to say for sure who they were.

To test if superficial changes to a face could deceive others, researchers recruited 13 men and 13 women aged 23 to 40. They were asked to provide a photograph from up to four years ago, then change their appearance for another picture.

Although the changes were superficial, those shown the picture pairs recognised the disguised person only 60 per cent of the time. That compared to 95 per cent using a second picture which looked similar.

Dr Eilidh Noyes, the study’s lead author, of the University of Hudderfield, added: ‘Deliberate disguise poses a real challenge to human face recognition.’