Unregistered

hello. we have a painting some believe to be a work of William Collins; others disagree - of course it is unsigned. there is no-one available on allexperts.com to ask an opinion. i would like this painting to be identified one way or another. Collins was a royal academician, but the royal academy library is 3 weeks behind with answering mail. anyone have any quicker suggestions? photos available. thanks a lot for any help you can give.