I had a chance to visit David Rumsey and his map collection (which this map is a part of) at his home in 2013. The breadth of that collection and this man's dedication to maps is fantastic.

This is a picture of his 2013 digitizing setup: https://www.flickr.com/photos/rhodes/9066129105 which he built in what was basically his garage. I don't remember much technical detail about it.

I believe (part of?) the collection has since moved to Stanford.

The collection's web site is a great resource and fun to explore for anyone interested in maps. There's even a link to view part of the collection in Second Life.