In celebration of the 50th anniversary of BBC science fiction show Doctor Who, we revealed the 'real' face of The Doctor. Through the use of cutting edge face averaging software, post-doctoral researchers Dr. David Robertson and Dr. Robin Kramer have created an average face for The Doctor, using images from each of the Time Lord's incarnations.

Fans will be delighted to know that this average face was created using all of the thirteen known Doctors, including the 'War Doctor' played by John Hurt, as well as the latest actor to fill the role, Peter Capaldi.

This face average provides a remarkable insight into the true identify of the mysterious Time Lord. As you can see, the face is not dominated by the features of any one of the actors to have played The Doctor. Rather, the face represents a combination of the averaged features of each actor to have taken on the role

Current research at the Face Lab focuses on investigating the problem of within person variability in face recognition. Dr. Robertson said, "While The Doctor represents the extreme form of this line of research, in that he takes on an entirely new face after each regeneration, in the real world people do keep the same face but their face still varies considerably across their lifetime and in photographs. This variation can be caused by the natural ageing process and changes in expression, pose, lighting and hairstyle. Indeed, we have all heard the phrase 'your photo looks nothing like you', and our research focuses on how we are able to recognise a person when we know that their face can vary considerably under different conditions'.

Dr. Kramer said, "Research by our head of lab, Professor Mike Burton, and colleagues, has shown that we are excellent at recognising people that we are familiar with. For example, if I was to show you 30 photos of Tom Cruise taken over his 30 year acting career, it would be quite easy to recognise him in each of the photos, despite all of the changes in his appearance over that time. However, if you did the same thing with someone you were unfamiliar with, you could find it much harder to spot that all of the photos showed the same person".

Understanding how we are still able to recognise a person given how much they can vary and why we find this easier for familiar compared to unfamiliar faces is important in a number of real world situations in which face recognition is vital. For example, passport control officers have to match unfamiliar faces to their passport photos, while those who have witnessed a crime may have to identify an unfamiliar perpetrator from a police line up or a low resolution CCTV image.