Hi All,
Sorry I missed the Ass and forgive me if I'm late to the party, but I think I can help:
Camera is fine -- the other two photos you posted don't indicate any problems with the camera.
I did a real quick down and dirty edit on this one to illustrate what's at the root of the problem. It's the scene lighting. Look at the inset histogram. You see data that suggests there are two photos here. THERE ARE TWO PHOTOS HERE, and you've squeezed them into the space of one photo. On top of that your camera meter wasn't sure what to do and in classic Canon style it got conservative and protected your highlights -- good thing.
It was suggested earlier that the highlights are blown; no way, it's quite the contrary.
The gap in the histogram that I've marked as problem is the space between earth and sky. When that space is a gap like you see here, you've got trouble. Notice that the entire "earth" section of the photo doesn't even get past the halfway mark. The photo is solidly sidelit with a backlight sky. In a case like this you've got three choices:
1. The camera can expose for the sky and underexpose the foreground.
2. The camera can expose for the foreground and blow the sky.
3. The camera can try and stab for the middle and screw up both ends.
1. You lose.
2. You lose.
3. You lose, but you might salvage something in post if the camera holds the sky.
The noise you're seeing in the photo is as Bitter first called it: underexposure. The camera had no choice.
Take Care,
Joe