From submitter Miriam J. Robbins:
My great-great-great-grandfather, Sylvester Fredenburg (1844 - 1879), who served in Co. A, 50th New York Engineers; Co. I, 33rd New York Infantry (twice); and Co. L, 50th New York Engineers. Photo c. 1861-4, probably in the Town of Jerusalem, Yates (now Potter) Co., NY.
Nice, but the damage to the image drove me to restore it: http://tmblr.co/ZMDc9xJBr84R