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Various resolution downloads:
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Technical description:
The MegaPrime upper end is not the only
one in use at CFHT. In this picture, it is seen sitting on the floor ready
to take its first ride, fully equipped, to the telescope. In the foreground
is the F/8 upper end, holding the secondary mirror used when observations
have to be made at the Cassegrain focus of the telescope.
The MegaPrime upper end can be identified by its black and silver cover.
In the background is the old prime- focus upper end, currently housing
CFH12K.
Astronomers used to spend hours in the "cage" - the black cylindrical
structure on top of the upper end. As CFH12K is decommissioned, its upper
end will be used for the Wide Field Infra-Red Camera (WIRCAM),
the next CFHT wide field imager in development.
Observing modes from prime focus to F/8 involves swapping the upper
ends. It is generally done twice a month: dark nights, around New Moon,
are often used for imaging the visible. Bright nights, around Full Moon,
are mainly devoted to the spectroscopy of bright objects or infrared observations,
which are not greatly affected by the presence of a bright Moon.,
Credit line: "Canada-France-Hawaii Telescope
/ 2003"
Copyright © 2003 Canada-France-Hawaii
Telescope Corporation |