Possibly identified as Alonzo F. Thompson of Company C, 84th New York Infantry Regiment (earlier known as 14th Regiment New York State Militia). (Source: Martinez, Ramona. Photo Mystery Solved, Then Doubted, Then Deciphered, Thanks to Readers; http://www.npr.org/blogs/pictureshow/2012/04/17/150801239/)
Medium: 1 photograph : quarter-plate tintype, hand-colored ; 11.1 x 9.5 cm (case)
Liljenquist Family Collection of Civil War Photographs; Ambrotype/Tintype photograph filing series; Library of Congress Prints and Photographs Division.
Record page for image is here.
Civil War Portrait 015