V&A has a print room you can visit but it's a bit slow - only a patient photographer waiting to see real photographs in the flesh with no glass in the way will understand waiting to see some pictures for 5 minutes. It's free but they don't allow pens and anything bigger than a sheet of paper (or thereabouts) into the room. Check your items into the cloakroom on the ground floor (sub-ground floor? near the subway entrance), take the lift up to the right floor and you'll find it easily. Can't remember which floor off hand. You should also have a list of what you'd like to look up to ask to be brought out as it's not a browsing sort of gallery.