This is Thomas Floyd Barron, my maternal grandfather (with guitar) and his brother-in-law, Vester Whitlock. They married sister, Bertie (my grandmother) and "Effie" Allen.
Everyone called my grandfather "T.F." (Thomas Floyd). He was born in 1896 and this picture was probably taken in Alabama circa early 1920's. T.F. was a steam shovel operator and his favorite singer was Jimmie Rodgers.
I keep this picture in my guitar case and see it every time I get my 310 out to play.

(Sorry if the picture is too big.)
edit: Well, I posted it and the picture is HUGE. Maybe my son can show me how to resize it tomorrow