Thanks for the suggestion
there isn't any "logical link" between tags and albums, you can combine tags, but not tag with album.
what you can do is to tag all your pictures in the album "Sunset" with the tag "Sunset" then use the [redirect] option of extension:175 to redirect the album to the tag page
then the user can click on the "+" sign near the tag "Water" to browse through pictures tagged "Sunset" and "Water"
I know.. i's a bit tricky ^^
I wanted to make a suggestion about how tags work when you are inside a particular album.
For Example, lets say I have two Albums
Album 1: Sunsets
Album 2: Animals
Now if I am in the "Sunsets" Album and select the "related tags" water the system gives me EVERY photo that has a tag of water, even if that photo is not in the sunset album. I would expect that the related tags option when inside a particular album would only work on the current album.
I just wanted to pass that along as a suggestion since I think it's the logical way the tags should work when you are in a particular album. I suspect that if a user is viewing the "Sunset" Album and picks the related tag of water that they really want to see only Sunset photos with water in the photo in that situation and not a cute kitten that got all wet.