Where the Norwegian chapter can be helpful is in letting us know how such a thing might play out if we were concerned with pictures from Norway's national gallery.
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I guess you are speaking about GalleriNOR, which is a joint effort between Nasjonalbiblioteket and Norsk Folkemuseum. Sorry for my rotten english, but I guess the information is more important than the grammr! ;)
In the case of GalleriNOR several people uploaded images from the site without prior agreement with neither NB nor NF. After a while I get in touch with them and asked how we should handle the case, what people believed was the right thing to do from our side and what NB and NF wanted to do. First the stand was established as "the images must be deleted" and "we don't want to delete them", then we said "okey we will attempt to get them deleted through due process - but hey, how much of the traffic come from our site?" Then things get a bit amusing. The thing is, about 60% of the traffic originates from Wikimedia Commons and with the additional internal traffic generated from this we probably generates over 80% of the traffic on the site. This isn't neglible amouths of traffic on a site, removing the images on Commons would pull the plug on the majority of the traffic.
So the situation are they said they would not claim copyright on their own copies of works in public domain. The wording in Norwegian is slightly different but the net effect is about the same. They would although forward any claim on copyright that isn't in the public domain as no doing that would put them in an awkward position. Photographers that are clearly dead early enough for the law to apply would not be a problem, that is Axel Lindahl.[2] Photographers that died later and are in the "snapshot category" compared to the "work of art" are difficult. Typically this is Anders Beer Wilse.[3] The fist has a shorter time limit before they go into public domain. Our "understanding" is that we may claim a photo to be a snapshot but we may get a notice that a specific image is a work of art. In that case - woopsie, our fault, we start the process to remove it, no problem. We can't although get a written statement upfront from them wetter a specific photo is a snapshot or not simply because they are not in a position to make such a statement, its something the heirs has to agree upon, and probably the court if so. In that case we have more than enogh time to remove the images.
As a note, for the moment there is quite a lot of images uploaded that are taken by Wilse, and I think they should be carefully examined to verify that none of them are in the category "work of art". It would be a shame if we upload images that creates trouble between us and NB/NF. Probably we need a writeup about some general guidelines, but if we can do without such a guideline it would be better.
NB/NF are asked if they want to join us in some future talks about how such images can be better utilized. For them it is a real bonus to get the traffic, especially that the images are of fixed resolution on Commons, as that makes it possible for them to add services to their own site, like selling copies of higher resolution. Sometimes it seems like people forget that we must cooperate with the museums and galleries to create a win-win -situation.
One of the things they are very eager on is to be able to add additional information to the images. When we add photos to an article on Wikipedia that will create additional information about it. Admins on Commons isn't very eager to utilize that additional information, but that is a prime selling point for those kind of pictures. I guess we need to really rethink how we can utilize the new world of mashable sites. How can GalleriNOR rip out the information we add to the images and reuse that on their own site?
A few days ago there was a contest in the newspaper (website only) ABC Nyheter where photos by Carl Curman owned by Riksantikvarieämbetet was localized.[4] Those images were from about 1890. Within hours they were pinpointed to locations in Valdres, Norway. This is extremely valuable for museums as images suddenly become part of history.
[1]http://www.nb.no/gallerinor/ [2]http://www.nb.no/gallerinor/fotografer/lindal.php [3]http://www.nb.no/gallerinor/fotografer/ab_wilse.php [4]http://www.abcnyheter.no/node/90741
John Erling Blad Wikimedia Norway