Photographer creates picture of 100-man orchestra… with the same person playing each instrument

Why did it take 400 photos?

10,000 x 20,000 pixels is 200mp

Seems very unnecessary when you can cover that with about 30 photos

Then the extra 100 photos of the individual subjects…

Just the time alone seems too long for this project.

Source Article from http://www.dpreview.com/articles/9342358489/photographer-creates-picture-of-100-man-orchestra-with-the-same-person-playing-each-instrument