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Old January 13th 04, 10:58 AM
Jouni Tulkki
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Default Spirit color wheel not being used?

Conan Ford wrote in message news:gXuLb.33126$JQ1.9617@pd7tw1no...
I wonder what the purpose of the color wheel is, when I see images like
this:

Go to http://photojournal.jpl.nasa.gov/cat...=pia05015click
on the high resolution version and then click on the Full-Res JPEG, (or
TIFF it you want). I've linked them below as well. Incidentally the
medium res version is missing part of the center of the picture.

medium res:
http://www.jpl.nasa.gov/mer2004/rove...2004/video.jpg
high res:
http://photojournal.jpl.nasa.gov/cat...umber=pia05015

the colors on the color wheel do not at all look like the color wheel
he
http://www.jpl.nasa.gov/mer2004/rove...s/image-2.html

Specifically, there is no green or blue visible on the color wheel in
the mars images, unlike the images on the page showing the color wheel
alone. In addition, the blue has been changed to a brilliant red. I'm
wondering the point of a color wheel when it does not appear to be used
properly.


This is because most images have been taken using L2 (infrared), L5
(green) & L6 (blue) filters. Using infrared filter makes a big
difference to the calibration colors, because of the paints that are
used. The difference between infrared and red in mars lanscape is much
smaller. In other words, even though the color wheel looks strange,
the landscape should have quite realistic colors.