Hmmm... This at least seems to have an L4:
http://marsrovers.jpl.nasa.gov/galle...1P2262L4M1.JPG
http://marsrovers.jpl.nasa.gov/galle...1P2262L5M1.JPG
http://marsrovers.jpl.nasa.gov/galle...1P2262L6M1.JPG
And this is the L2
http://marsrovers.jpl.nasa.gov/galle...1P2261L2M1.JPG
As far as I can see the combination of these by using L4 and L2 are not to different, the L2 version has more cyan in it, but I dont know how to calibrate for the cameras sensitivity. The RGB channels of the resultant picture seems to have a similar intensity profile, probably the imaging system optimizes it(so that the picture fills the entire grayscale), so that it isn't too dark, but since this is done on a grayscale basis, its hard to accurately compensate...
Anyway, I don't think the point of the mission is to answer what color the ground and sky would be to someone standing there(color is subjective, the eyes would adapt to the light and so would see something different than what the camera sees), the filters are there to help the scientists do an initial identification of the geology of the site, before employing the MiniTES and spectrometers, and for this I think the IR filter might be better suited. And it is going to be mapping the site in 3D...
10% of bandwidth is quite a lot, I think the com.windows is quite full as it is.. And it seems if one were to take 1 extra picture, this would stand for 20% of the bandwidth used by the Pan Cam in a color set(L2,R2,L5,L6 is an often used combination, it seems)..
Now I don't know what the public thinks about this over in the USA, But here, people doesn't go demanding the money back be course the water in the travel catalogs looks bluer than real life, or the photos in the album isn't exactly the same as RL... People are used to pictures not being true color. Why one should think the images from the rovers are any different, I don't know... Its not like other pictures of the universe is done in true color. I might be wrong, but I think its how the light of each frequency is reflected that is important, and perhaps to compare pictures of two frequencies, and i would think mapping false color would be more suited for that than watching a true color image...
Anyway, color might be eye candy, but for a truly dramatic picture you can't beat grayscale... :P
