QUOTE (elakdawalla @ Jul 24 2006, 07:05 PM)
This reminds me that something I've been wanting to see for a long time is a composite view of Saturnian system bodies shown with the same processing applied across the board, to illustrate the differences (if any) in albedo and color among them.
I've been wanting to see that as well, because as I was fiddling with the PDS data, I noticed there were stark differences between brigthnesses of various moons. I was too lazy to make a systematic comparison until now.
Below is a montage of the major moons -- except Phoebe, I couldn't get a darn good RGB set on the PDS.
All composites are approximately true color and use the same brightness scaling. I used Enceladus as the reference maximum brigthness.
The moons are from left to right:
Prometheus, Pandora, Mimas, Enceladus, Tethys, Dione, Rhea, Iapetus, Hyperion and Titan's limb on the right edge. All moons were scaled to the same scale, showing how they would appear to the narrow angle camera at a distance of 500 000 km.
A note on observed brightness -- it's a function of phase angle so I preferred a single phase angle or as close to it. It wasn't always possible, however. Notable exceptions are Prometheus and Pandora with phase angles of 10 and 19 deg, respectively. Other moons are at around 50 deg, except Dione and Rhea - 39 & 34 deg.
You
may note that the leading hemisphere of Iapetus is practically invisible at this brightness scale. At albedo of around 0.04, the dark side is really pitch-black. Hyperion and Titan are very dim as well.
If I can dig-up a good RGB or IRGUV set of Phoebe, I might add it as well, but from what I've seen it's pretty gray and only slightly brighter than Cassini Regio.