Some bandwidths of visible light are:

Everything gets kind of fuzzy from this point on. The visible light bandwidths are not even sharply delimited. The bandwidths in the Martian cameras don't necessarily match the color bandwidths on Earthling computers. In a lot of the images some of the bandwidths are missing. For example, this image:

      

only uses filters 4, 5, and 7, which more or less correspond to reddish-orange, yellow-green, and violet. There is a hole or two in the spectrum, notably red and blue, so it ends up looking a little weird. But it's still much better than black and white.

Some of the images from Mars use filters 2, 5, and 7, or some wide range like that. This provides more information for scientific analysis, but it doesn't look normal when combined. That is, if there is a "normal" for pictures from Mars. I skipped most of these.

The right pan camera filters are mainly longer wavelength in the ultraviolet range. I only included one of those pictures, mostly because I wondered what it would look like:

      

I used Photo Mud to merge the separate images. In fact, I wrote the Merge Color Separation function in Photo Mud so I could do this. You can download a test version here:

      http://xpda.com/photomudsetup.exe

When Photo Mud version 3.0 is released in a few days, I'll replace this file with a 30-day trial version. If you download the test version before then, you can have a free update to the release version without a 30-day limit. Let me know if you find any "design considerations" or other things that don't work.

Here's where to get the latest raw images from Mars:

      http://origin.mars5.jpl.nasa.gov/gallery/all

Some of the NASA pictures show mainly red on Mars, such as this panorama:


 

But the colors in the corners of this sundial in the base of the photo from looks quite a bit different on earth than on the landscape photo. There is a lack of blue in the Mars photo, or maybe even a translation of blue to red. There's probably a good reason for this, since NASA has better software and spent more time on it.

It looks to me like NASA included filter 2, infrared light, in their red color composition. In this image with filter 2, you can see how bright the lower right color tab is:



This one is filter 3, is visible red. The blue tab in the lower right is not nearly as bright:



Here is a composition I did using infrared as red, and shifting the colors toward that end of the spectrum. This is kind of like the sundial in the color landscape.



Here's the image with "normal color" composition:



The second one looks a lot closer to the original photo above. In these two images, the background dirt looks about the same, but these settings make a big difference sometimes.