Collecting photographs of the rich and famous can prove to be a lucrative pastime. In London this week, photographs of Hollywood beauties, Jean Harlow, Greta Garbo, Elizabeth Taylor, Marlene Dietrich and dozens of other leading ladies go on sale. Bonhams, which is organising the auction, reports an upsurge in interest in such items in recent years, with photographs increasingly being seen as works of art.

Other lots to go under the hammer include a 10-picture set of Marilyn Monroe by Bert Stern taken shortly before her death. These pictures, which are signed by the photographer and were limited to 250 issues, have been valued at between £5,000 and £8,000 sterling.

The EU does not yet consider a photograph to be a work of art, unless it is limited to 30 or fewer copies and the photographer has made the prints himself or supervised the process. Anyone collecting photographs should note that photographs will be worth more if they are revealing.

Investors should also search for a signature, or at least a photographers stamp otherwise these snaps are practically worthless. And remember, the copyright of the photograph rests with the photographer and as such investors may not sell them for publication.