I don't know, and somebody may give a better answer; but I'm guessing that an expert would need to see the item personally to value it properly. Minor details count; so does condition, which is hard to tell on a photo; so does being able to see all sides of it.
To get a broad idea, why not enter its name into something like eBay and see what similar objects sell for. Or just Google it plus the word "price".
Jno's spot on. No reputable valuer would give an opinion based on a digtial photograph alone.
However you might interest an aucton house in coming to you to give a valuation, on the basis of a digital photo - especially if the object is difficult to move.