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Old May 28th 08, 08:56 AM posted to rec.photo.digital.slr-systems
Chris Malcolm[_2_]
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Default NASA's Mars probe: NO cmos, NO Bayer

John O'Flaherty wrote:
On Tue, 27 May 2008 19:53:23 -0700, Voodoo Thunder Pig
wrote:


RichA wrote:

from Amateur Photography magazine;

The camera has a double Gauss lens system, a design commonly used in
35mm cameras,' explains the space agency.
'Images are recorded by a charge-coupled device (CCD) similar to those
in consumer digital cameras. The instrument includes sets of red,
green and blue light-emitting diodes (LEDs) for illuminating the
target area.'

Nasa claims that the camera can focus down to 11mm and record images
at a resolution of '23 microns per pixel' at the closest focusing
distance - allowing the camera to show details 'much finer than the
width of a human hair'.



This means tri-colour imaging through three different filters onto a
monochrome CCD.


Nice try, Captain Obvious, but that's not what it means. It means the light
sources providethe three colors, and no filters are necessary.


Do you mean that the different colors of LEDs are on at different
times, providing color separation? I wonder if they might also use
filters on the LEDs, though, to increase spectral purity of the
colors.


Most unlikely. The problem with LEDs as light sources for photography
is that they're too spectrally pure.

--
Chris Malcolm DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
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