Irrespective of anything else, it's much, much too sharp. Civil War cameras had long exposure times, and any but the slightest movement would result in a blur. Those gunners could not be standing stock-still in those positions.

That's one reason why there are no CW pictures of actual battles. Outdoor CW photos consist mostly of people standing stiffly in ranks or sitting around (occasionally on horses) doing very little.

Furthermore, the clarity of detail and the evenness of the lighting is beyond the capacity of Civil War photography.

Look at any collection of authentic CW photos and you'll instantly see what I mean.

MY favorite "Civil War photograph," which you can probably find online, shows Union troops exhibiting the carcass of a giant pterodactyl that they seem to have brought down with their rifles. Could it be a fake?