Of the three stereo camera systems on the Mars Exploration Rovers (Pancam, Navcam, Hazcam), only the Pancam is capabile of taking color images. In actuality, the images that are taken on Mars are always a single color and appear like a black and white photograph. The pancams have a color wheel (with 8 different colors), which puts a filter that allows only a single color of light to pass through to the camera. Unlike a digital camera that you can buy at the store, the color images from the MER panoramic cameras need to be recomposed from individual colors. There is an additional difficulty in that eye of the two pancams are have a different set of filters in their respective filter wheels. The left eye has colors though the visual wavelengths and the right eye has colors that extend into the infrared (longer wavelength than red). Thus producing color stereo images are a particular challenge. Further down on this page, we have put together an interactive program that demonstrates how colors from the pancams are put together to approximate what the human eye would see on Mars.