Wow, what a great photograph this is; thank you so very much for sharing it with our WikiTree community! I find myself wondering whether the younger man to the right be one of Alfred's sons--and if so, which one?
I also wonder whether this photo might be possibly scanned at higher resolution so that it could be "zoomed in" on to see even greater details than are likely visible to the naked eye when viewing the actual photograph.
I wonder if this picture was taken in Canada or in Michigan--and I'm guessing it was likely taken in Michigan, based on my guess of the age of your great-grandfather in this photograph.
You can view maps of Flint, Michigan circa 1900 through the Library of Congress, which can be a lot of fun if you happen to find Census documents showing your great-grandfather's address: