Digging out my notes, I see those date back to 2008 and relate to CS3 Extended.
However, the relevant bits seem to be:
* Median Stack Mode, "which eliminates pixels that aren't consistent from frame to frame."
* Attempt to Automatically Align Source Images.
And a follow-up comment:
"I think you can also do something similar in regular CS3. Take multiple shots of the same subject area and load them into a document with each image on its own layer. Then use Auto Blend Layers. This will remove objects which aren't common to all of the images."
I've been meaning to try this before posting a response, but haven't gotten around to it yet. Perhaps you will!
