There was been quite a bit of gull identification talk of late. Many people said that the best (only?) way to get to know the Laridae is to get out in the field and study them. I agree, but there is a second possibility.
Many years ago, during a temporary lull at work I spent about a month from dawn to about 9AM at the fabled 'Pellet Plant' just over the bridge and to the south on Sauvie Island, after which I headed into Portland to work. It was no coincidence that my visits coincided with reports of a Slalty-backed Gull on the island. It took awhile before it (they, actually) showed up, which they did. I never saw anyone else, but one time I ran into the vaunted Harry Nehls who asked why I was taking photos of all the gulls. I answered that I was documenting all the gulls that weren't Slaty-backs. He laughed, but it was true. I took photos of a_lot_ of gulls, some of which were/are very interesting. This was in January about 20 years ago. These were all slides that I long-ago scanned to digital format. So.........
If there is sufficient interest I could start posting these photos a few at a time and interested parties could identify them. Undoubtedly a consensus would be reached in most cases by the experts (not me), but a few may be somewhat ambiguous. I would then combine the ID responses and post the results.
This will be a lot of work for me, so it's not worthwhile if there is little interest. If I get 10+ offline replies of interest I'll think about it; If I get 20+ I'll start on it in the near future, just in time for the upcoming gull season. Now if there are few responses to the first group posted I won't continue. Hard for me to guess how much, if any, interest there might be.
If there is sufficient interest, the way I'd prefer would be for people to communicate their ID independently rather than forming a group consensus Then we would could see the differences among birders, whether expert, experienced, or novice. And of course, there could be comments on individual IDs after the consensus was posted