Poor John Calvin. He had the great misfortune of living before the invention of the camera.
As someone quipped in a previous post, if you are writing a book on Calvin, which portrait do you use? Here's a sampling of just a few of the familiar images of Calvin.
I guess the image you pick will largely depend upon your view of Calvin. If your take on Calvin is favorable, you use one of the more youthful portraits. If your take on Calvin is more negative, the temptation would be great to use one of the portraits where Calvin looks like he just passed a kidney stone (which was just one of his many physical maladies).
Luther left behind a plaster death mask. I've seen it, and its rather creepy because Luther was so swollen at death. But we know what Luther actually looked like. My assumption has always been that the best (most accurate) likeness of Calvin is the drawing with his name in Latin (picture one, row one, and picture two, row two).
As he ages, Calvin appears increasingly gaunt and haggard in most of the paintings, no doubt indicative of his declining health. But his familiar cap, Z.Z. Top beard, and fur collar are consistent throughout.
I'd want someone to paint my portrait when I was about thirty, had hair, and was still in somewhat decent shape. I'll bet Calvin would prefer the first portrait in row five. But that's sure not how most people think of him.