The Public Domain Jupiter Image was Supplied by NASA/NSSDC This Site Not Endorsed by NASA
Note: The images in the below illustration are bigger than actually seen
through a telescope, but give a sense of the details seen through the
respective instrument. As telescope size is decreased, less detail is apparent,
and image size for given focal ratio is reduced.
Notice also that with small aperture telescopes, the image of Jupiter
appears mostly in shades of gray, with more color being apparent as the
telescope aperture increases. The reason for this is that the detail acuity of
the human eye is more sensitive than the color detection. Until there's enough
intensity in the image to sufficiently stimulate the color detection mechanism
of the eye, the perceived result is a gray object. As telescope aperture
increase, the light intensity of the image increases, causing enough stimulus
for the eye to perceive color.
Other factors enter in to viewing clarity, such as atmospheric
turbulence, telescope focal ratio, and secondary size.
