Yes I am aware of what the "norm" was and collar rank, but there were some CS that did wear shoulder boards as I have seen numerous photos of that. And the one I have of a 4th SGT from teh 1st Ark Inf, was taken in early 1862 per his letter to his family when he sent it and it does have shoulder boards and there is no sleeve rank on what he is wearing.

As to the US soldier photo I have, he is a CPL at his highest rank but he is wearing a us frock coat that has shoulder boards but nothing on them denoting any rank. He too, has no shoulder rank. He too enlisted in early 1862. That is why I was checking to see if anyone knew if it was common for soldiers to borrow their officers coats for photos or if the photographers had extra coats they would use as well. These soldiers never attended military schools and neither was in any pre war militia unit, so that is why I asked.