Do you know this man?

Manchester Art Gallery has got a quick task for everyone. Have a scan of the photographs below to see if anyone looks familiar. They're featuring in the gallery's new exhibition of portraits by Dorothy Bohm, one of the country’s leading photographers. She took them in Manchester in the 1940s and 1950s while she was studying at the Manchester College of Technology and during her early career at Samuel Cooper Photography Studio and at her own Studio Alexander in Market Street. Only problem is, the gallery doesn't know who these people are.

Dorothy’s early prints and portraits will be displayed in a reconstruction of her studio and there'll be a replica darkroom to demonstrate the now almost forgotten technique of black and white photographic processing.

If you recognise any of them (Is that your grandma in better days? Is there a trace of your mother in that little girl's smile?) then get in touch with volunteer researcher Jennifer Boyd at aworldobserved@googlemail.com. There's a full gallery of unidentified portraits to look through here

Says Jennifer: “You can also check your old family photographs to see if a Studio Alexander portrait is hidden among them. The Studio distinguished its photographs by a number of methods: some may have the handwritten signature of 'Dorothy Alexander' in the bottom right hand corner, some may have 'Studio Alexander' printed on their mount or handwritten on the photographs themselves and some may even be housed in folders which have the full name and address of the studio printed on the front. We’d be really excited to hear from anyone who can help us with our research.”

Please send copies of photographs together with contact details to: Jennifer Boyd, c/o Exhibitions team, Manchester Art Gallery, Mosley Street, Manchester M2 3JL or email aworldobserved@googlemail.com.

Anyone who provides Manchester Art Gallery with copies of their Studio Alexander photographs will be given a free copy of the exhibition catalogue, worth £14.95. Their photographs will also be added to an album of recently discovered Dorothy Bohm prints that visitors to the exhibition will be able to browse.

The photographs will be on display as part of the photography retrospective A World Observed 1940 – 2010: Photographs by Dorothy Bohm, which opens at Manchester Art Gallery on 24 April (until 30 August). Dorothy’s early prints and portraits will be displayed in a reconstruction of her studio and there'll be a replica darkroom to demonstrate the now almost forgotten technique of black and white photographic processing. Over 200 photographic images will be shown, tracing Dorothy’s photography career over more than six decades and several continents.

A World Observed 1940 – 2010: Photographs by Dorothy Bohm, 24 April-30 August, Manchester Art Gallery, www.manchestergalleries.org