autor of the photos is russian photographer sergei prokudin-gorskij, who was making color photos at the beginning of 19th century by making three different expositions to three different glass plates through three different rgb filters...

the images are absolutely breathtaking and i highly suggest to anyone who hasn't saw them already to check them. time well spent.

https://www.google.com/search?q=Sergey+Prokudin-Gorsky