I dont think the photographer changed anything... the photos were mistakenly relabeled many years after the war... repeatedly... Some one looked at it saw a US cartridge box and made a shallow assumption... also since there was an artillery sponge nearby... well he must have been an artilleryman... the guy in the background wearing civilian clothing more or less assumed to be confederate due to the use of civilian clothing articles... Some of these earlier assumptions tacked onto these photos remained stuck to it... others evolved as each publication cycle did its own take on them.... So at times you can find the same photo with totally different label on it.

Once those with more research knowledge reexamined these... it finally came to light the other details present... ie: the Tait jacket... the CS canteen strap, etc... The guy in the background is dressed as a civilian... but thats not always confirmation he was... Since these were taken a bit after the engagement and what exposure can do to some bodies... It is also an assumption that the guy might have been a servant... or could just be the case of post-mortem effects taking place, that would give one the impression of such.

Frederick