The owner has contacted the Daily Mail and the Brontë Parsonage and several experts give their opinion:

It is clearly a photo with a story to tell – and collector Seamus Molloy hopes it will earn a place in the history of literature. For he believes the subjects in the grainy antique picture, which cost him only £15 on eBay, are Charlotte, Emily and Anne Brontë. If so, it would be the only known photo of the sisters. Mr Molloy, 47, bought the 4½in by 3¼in image because he thought its subjects resembled the Brontës in the only known surviving portrait of them, painted by their brother Branwell. (...) Yesterday Catherine Rayner, of the Brontë Society, said: ‘It would be wonderful if it is. It is worth investigating. 'We have discussed it and there is a possibility it might go forward for some sort of forensic examination. 'Most of me is saying I don’t think it can be them. But we are not dismissing it.’ Ann Dinsdale, of the Brontë Museum in Haworth, West Yorkshire, said: ‘It seems unlikely that the Brontës would have been photographed. 'Photography was in its infancy. The family was quite reclusive and Emily and Anne were unknown at that time. 'Naturally there is a huge interest in what they looked like. However, provenance of images is hard to establish and sadly we may never really know.’ (...) Mr Molloy has also contacted the National Portrait Gallery, where photographs cataloguer Constantia Nicolaides said there were ‘notable differences’ in the brow lines and lip shape of the subjects in the photograph from those of the sisters as painted by Branwell. Two historical costume experts, contacted by the Mail without being told it was believed to be a photograph of the Brontës, dated the clothing worn by the women to around 1850 - tantalisingly close to the latest date it could have been taken, 1848 when Emily died. The National Media Museum in Bradford told Mr Molloy the image is a ‘collodian positive’, a process that was commercially available after 1852, and doubted a photographer would have used that to copy an even earlier form of photograph as it would have been ‘practically difficult’. (David Wilkes)

If this is a real picture of the Brontës, then I'm Heathcliff! (...)
Emily, after years of withering away, died of TB in 1848, Anne a year later. All, in this photograph, look as healthy as three Yorkshire puds. This photograph would have had to be taken in the 1840s, when photographic portraiture was in its infancy. This trio have left, the eye suggests, their infancy some way behind them. The one on the left (with a prayer book in her hand) looks middle-aged. Exposures, for the earliest photographs, took many minutes (trees were, for that reason, favourite objects: it can get boring). (John Sutherland)

You’ve got to think, why would there be a picture of them? There’s certainly no record of them ever having had a photograph taken. Everybody wants to know what the Brontës looked like – I regularly get sent images, either portraits or photographs, of either one woman or three women, and people think that they’re the Brontës. We do what we can, but if the image has got no provenance and it’s not documented anywhere, it’s really difficult. Even if you can look at it and say, ‘well the hairstyles are absolutely right, the costume is right,’ it’s still difficult to know for sure. (Ann Disndale) 

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