Typical RGB values for recording and display are Red-600nm, Green-530nm and Blue-480nm. As we can see these coincide with the L4, L5 and L6 filters on the PanCam. The difference is, in this panorama image, and in most images taken by the Rover, the L2 is used for the Red-Channel instead of the L4. The L2 is at 750nm, and right at the extreme end of the visible spectrum, the near infra-red range. This increases the range of the spectrum that can be recorded by the PanCam, allowing higher definition to be recorded, making it easier to see into the shadows and so forth.

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Some people have posed the question, 'why doesn't NASA tell us all this on their site'. The simple response is 'why would they?'. The images shown by NASA are as close to the actual appearance from the surface as they can get. The colors are as true as a hundred million dollars worth of camera and image processing software can get them. As accurate as any digital image can be.

There is simply no point in adding on their site "caution these images are not 100% precisely actual colors" when no digital image is really 'actual colors'. It would just give the conspiracy types more things to panic about.

We can already see for ourselves that the color of the ground and sky shown in the released panoramas is correct. There is no suggestion whatsoever that any modification has been made of the data coming in from Mars.

Learn almost everything you ever wanted to know about digital color images, especially those coming from Mars here, from the Above Top Secret News Network.

It's all in the eye of the beholder.

S