...as I suspect REB thinks I'm full of shit here.)

When you get out of Astronomy 101, give me a yell. You can even make it a REBel yell.

Going THAT route, eh? Well, then I called you 6 years ago and you missed it. Call ME when you get out of trigonometery.

You still can’t explain why that area was processed as the darkest area of the picture.

Not processed as the darkest area, IS the darkest area and as a result coded as black.

It was not because it was a shadow, as you had stated, but because there is some dark material in those gullies.

So you maintain. You sound very certain, did you sneak off in your spaceship and have a taste? Please REB, throw me a bone here.

Like I said, you can not get shadows-even light ones that are artificially darkened by computer processing,

I don't think it's computer processing, it's a fundamental characteristic of how the MOC CCD functions.

at 1:30 pm on a summer afternoon. Not on Earth, and not on Mars.

Hmmm, it doesnt depend on latitude or orbital inclination or the local slope or sunlight intensity?

Do yourself a favor, draw what you think a cross section of these gullies would be.
Then draw a 65 degree angle (solar altitude during first MOC image in question) ray touching one edge of the gully. Note where it falls on the other side of the gully. Then tell me again why there cant be shadows never, no-how at this time.

Now, that's a little different case than whats actually going on in the picture but I think you might find it......enlightening.