I'm going to upload those photos onto a folder at Webshots (see my link in my signature) called "Albany Amtrak photos." Check for them in a few minutes.
Anyway, the dome car was on the Coast Starlight, train 14(3JAN04).
Due to bad winter storms, Starlight service was screwed up. Several trains weren't able to pass through the Cascade mountains because the snow was so bad.
By the time I got to Los Angeles, things had cleared up somewhat, but service was still screwed up. In fact, our trainset, which was due into LAX the night before, was still about six hours out by the time we were to leave.
Amtrak just so happened to have a set of Horizons, plus a dome car, in Los Angeles that needed to go to Oakland for a Ski Train special. So, they gave us that set (we actually took it to Sacramento because it was easier to make the transfer up there), where we caught a regular set of Superliner equipment (the southbound Starlight due in that night was terminated in Sacramento because it, too, was running extremely late).
So, it was just a luck of the draw.