I just ran across a website with thousands of large format photos. Photos include the NYC & subsidiaries and locomotive manufacturers. I've only been searching it a short while, but have been pleased to find a number of NYC and MC photos from the 1800s and early 1900s. The photos are from the Joseph A. Smith Collection.
http://www.nyysa.com/archive/code/collection.php?e=1
http://www.nyysa.com/archive/code/collection.php?e=1