@lelliott19 @DOswalt Thanks so much for your comments!
The backmark is "Rasbury and Prophitt" of LaGrange Co. which supports a 4th GA image. However I don't know if that is the original studio that took the photo. I can't find any records for Rasbury and Prophitt together right off to help date the photo. Also, the CDV looks like a copy from a print rather than a copy from the original exposure so it could have been taken elsewhere. I will say that I am no expert in the field of CW photography so I do not know how all that worked.
LaGrange is in Troup County. In addition to the LLG (Co. B,4th GA), there was the West Point Guards (Co D, 4th GA). The WPG is the unit that Ernest's brother Albert served in, so even if it was a mislabeling of the wrong Chisholm brother he did not serve in the same company as Ware although there is a good resemblance of Ware and one in the photo. It could be that Ernest served very briefly in the LLG and with the holes in the records it just doesn't show. I feel like the photo is more 4th GA than Georgia Artillery.
What's the odds that Ernest's Artillery uniform in 1863-1864 looked identical to the known uniforms used in the 4th GA that his brother served in in 1861-2???