Sir Patrick Stewart had to have hundreds of hairs individually added to his face for 'Logan'.

The 76-year-old actor had to look like a ninety-year-old man for his role as Charles Xavier in the last instalment of the 'X-Men' franchise and now the movie's make-up designer Joel Harlow has revealed what lengths they had to go to to age Stewart in the movie.

He said: ''There is a lot of makeup on him that you can't pick out, because hopefully, it's very real. But it's those subtleties that happen to us as we get older: a thinning of the skin, and more subdermal spots and discoloration, and hair takes over your ears and eyebrows. So I was adding one hair at a time to Patrick's eyebrows and ears, but you might miss it if you didn't know it was there.''

The Oscar winning make up artist was pleased to have not been met by any protests when he had to work on making the actors look older and wrinklier for the movie.

He added: ''I had none of that in this. Everybody knew what movie we were making, and everybody embraced it. But certainly on other films it's been an issue. Everybody wants to present their best face, and usually it's my job to make them look great.

''This wasn't that film. It's a swan song for some of these characters. So everyone was on board with the vision Jim had, and there was never any vanity in the trailer. You couldn't have this story with vanity. It flies in the face of what these characters are going through.''

And Harlow admits it was tough doing the prosthetic make-up for the movie as they had to battle with the elements as a lot of the movie was filmed outdoors.

He told The Verge: ''Any time you're dealing with dirt or blood - you want to maintain continuity from shot to shot, and that becomes incredibly difficult when you're dealing with the elements. You dress blood onto somebody's forehead and then they do a stunt, and suddenly they've sweated the blood down across their face, and now you have to match future shots to that. Or you have to clean it all up and start over, matching up with your original.

''The environments we shot Logan in were incredibly grueling. There's a farmhouse sequence we shot in Natchez, Mississippi, in the middle of summer. It was a midnight shoot, and the mosquitoes were voracious. I don't think I've ever been bitten as many times as I was over that week and a half of night shoots. That was horrible.''