Here is a CDV by Brady from his later years at his Washington DC studio. The subject is R.J. Arnold, who went on to have a career as a photographer in California.
For more information about Mr. Arnold, there is a very nice website about California photographers from the 1870s-1990s at CAViews.com.
It is seldom that you find photographs of early photographers, so this was a neat acquisition for me. I have one other image that I believe is of a photographer (the label is vague – it could be the photographer himself or it could be merely inscribed by the photographer to the sitter).

Images of photographers with the tools of their trade are, unfortunately, extremely collectible and therefore out of my budget. But this photo of Mr. Arnold as a young man fills a nice niche as a stepping-stone to the goal of a cdv or tintype of a photographer with his camera.