Photos of imperial Russia

I was looking for some visual references and came across these photos of Imperial Russia. Author would make 3 snapshots of the same scene through 3 color filters - red, green and blue and then overlay them to get color picture.

Interval between capturing the pictures was about 1 sec. The main restriction that it object should not be moving. Here the description of the process - http://www.loc.gov/exhibits/empire/making.html

Kot-begemott blog - http://kot-begemott.livejournal.com/73148.html
Empire That Was Russia - http://www.loc.gov/exhibits/empire/

some examples of them:

Potential old man character

The hut of settler Artemij, who has been living on that place more that 40 years.

Trunk house and environment references