@ DMOC : What image hosting site do you use? I know photobucket has an option to show linked pictures at original size (the size the picture was uploaded with). I had the same problem you are having (picture being compressed to a smaller size making the text hard to see) and all I had to do to fix the problem was to set that particular option. Hope that helps! 
Global lurker ; played in Civ VI PBEM 4, 5, 15; DL suboptimal Civ VI PBEM 17
; played in Civ VI PBEM 4, 5, 15; DL suboptimal Civ VI PBEM 17