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Grasslands Observatory : Interesting Objects with Common Names |
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The Horsehead Nebula (IC434) |
There are many objects that have a common name associated with
them as well as a more formal catalog name. Some of these
unusual and beautiful objects are pictured here. Many of these color
images were obtained with the 24-inch f/5 reflector at the
Grasslands Observatory from 1996- to the present. They were
initially taken either with a Spectra Source HPC-1 CCD camera or
with an Apogee AP7 CCD camera. The HPC-1 contains a Texas
Instruments chip with a 1024 x 1024 array of twelve micron
pixels. The Apogee AP7 CCD camera contains a SITe 24micron 512 x 512 CCD chip that has
excellent quantum efficiency throughout the visible spectrum and
into the near-infrared portion of the spectrum.
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AP7 CCD camera attached to the 24-inch telescope at the
Grasslands Observatory. Notice also the
Isis FW1
filter wheel and
JMI
digital electric focuser. |
Exposures typically ranged from R = 1 minute, Green (V) = 1
minute, B = 1.5 minutes to R = 4 minutes, Green (V) = 4 minutes,
and B = 6 minutes for the Apogee AP7 camera. Exposures for the
HPC-1 camera were somewhat longer, especially in the blue (B).
In general, short exposures were used for bright clusters, and
long exposures were used for faint galaxies and nebulae. For
some objects, clear exposures were also taken and added to the
exposures through the photometric filters to produce a final
color image.
In
March 2001, a
Finger Lakes Instrumentation Dream Machine CCD camera was
installed at the observatory. This camera has a high quantum
efficiency SITe 1024 x 1024 twenty-four micron CCD chip. It
provides a nearly 28 minute field of view on the 24-inch f/5
reflector at the Grasslands Observatory. The Dream Machine is
used in operation with a Finger Lakes Instrumentation CFW-1
Color Filter Wheel and an
Optec TCF
temperature compensating focuser. The filter wheel contains
Photometric R, V, and B filters and also has an Open slot (O).
This instrument combination is now used for most of the imaging
on the 24-inch telescope.
Exposures typically range from R = 1 minute, Green (V) = 1.5
minutes, B = 2 minutes, and O = 1-2 minutes to R = 4 minutes,
Green (V) = 6 minutes, B = 8 minutes, and O = 5-20 minutes for
the Dream Machine CCD camera. Short exposures are used for
bright clusters, and long exposures are used for faint galaxies
and nebulae. Most color imaging now is performed using a
Luminance technique with Open or Clear exposures used for the
Luminance (L) part of the color composition.
Other instruments at the Grasslands Observatory include an 8-inch f/4 Meade LXD55
Schmidt-Newtonian telescope which can be mounted onto the side
of the 24-inch telescope and a Takahashi Epsilon 180 telescope
which can also be mounted onto the side of the 24-inch
telescope. Future plans call for separate mounts and
building for these telescopes.
Imaging with the Epsilon 180 and the Meade LXD55 was
initially done with a Nikon F1 film camera back and a Nikon D100
digital camera back. Now imaging on these telescopes is
performed with a Canon 20da digital camera. In addition,
the Canon 20da is also used with a variety of lenses including
15 mm, 50 mm, 80 mm, and 300 mm Canon lenses.
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Dream Machine CCD Camera combined with a Finger Lakes CFW-1 Color Filter Wheel |
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