Mauna Kea summit is definitely the place places with the highest
concentration of biggest telescopes on our planet (both Keck I
and Keck II telescopes are currently the largest operational
telescopes of the world). The summit is 4100 meters above sea level,
so approx. 40% of the atmosphere and 90% of water vapor lies below it.
Chill weather and environment quite unfriendly to life (and to many
devices, too) pays off in exceptional dark and clear night sky.
Even if the seeing at Mauna Kea would be considered exceptionally
good by many observers, big telescopes need the best conditions to
utilize their apertures. Seeing must be monitored e.g. to enable
changes in the observation program to fit current conditions. The
Canada-France-Hawaii Telescope (CFHT) is equipped with seeing monitor
based on continuous imaging of one star, splitted to three images by
G1-0300 CCD camera in the primary focus of the commercial
14" Schmidt-Cassegrain telescope
Mutual movement of all three images of single star indicates how
much the atmosphere distorts the image in the telescope. Exposures mus
be very low (approx. a millisecond) to capture the instant atmospheric
conditions. Seeing is then evaluated by a custom application and
published through Java applets running in the common WWW browsers.
Java applet displays measurement history
Of course we are very happy that MII CCD cameras were chosen for
this task and that our G series cameras proved that they can work
together with world class instruments.
The Keck telescope dome can be seen through th open slot of
the CFHT dome