Based on Chris Peterson's advice, I plotted a 166-pixel diameter white disk about where I'd guess the sun was.
![Image](http://permaconnect.net/mark/SaturnBacklit.jpg)
(I am partly just wondering if I can plot an image in this way.)
I don't have enough experience with photography to know any reason to place the sun off of the location of being centered behind Saturn. If the ring disk is tilted down about 27 degrees, then the rings are seen with sunlight shining through them. I don't see any tilt of the rings in this image either to the left or right, so I'm thinking that it is currently near the middle of Saturn's northern hemisphere summer at this time.
Why does the nearly-outermost ring appear like a bright white circle, while the rings within it are varying shades of khaki, or olive?