I'm not too sure why you think there've been no Viking Lander panorams. JPL has stitched together some, Washington U., and Calvin Hamilton; I've seen color panoramas in the Ames Image Library. They're out there, and not too hard to find.

The "true color" of Mars remains a bit elusive, though I think that "Hubble Butterscotch" is the closest rendering so far (superior filters in the camera), of Mars from space. I'm sure you remember controversies about the color shown in NASA's earlist releases of Viking Lander images--garish Day-Glo orange.

The problem is that the color reference targets on the landers deteriorated with UV exposure and got coated in dust. I've tried to use them as references, but they're hopelessly compromised.

As for a "white sky", I may have an approximation for you that I did myself. A while back I experimented with using the frost in several images as a white reference, balancing the color so that the frost came out (nearly) white.

21I091
22I094

As many people have pointed out, what I did was actually to portray what the surface of Mars would look like if it had a clear atmosphere. I don't doubt that Mars's atmosphere is routinely tinged by dust to some brownish-red hue, but I also think it's likely that there are days when the atmosphere is quite clear. At those times, Rayleigh scattering governs, and the sky should be dark blue (probably shading to black at zenith because it's so much thinner).

I almost wanted to say that since it appears that you Mars people can not make use of the data you already have, I don't see why you should have much more of it...

I almost wanted to say, "oh, gimme a break, E.P.". But I'll hold my fingers...

--Robert