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The early (1996-2001) black & white and color images displayed
in this website were obtained with an
Apogee AP7 camera (or its
predecessor, the HPC-1 camera) running under
MaxIm DL/CCD (Cyanogen Productions). The only image processing used for
the majority of the images was conversion of raw CCD FITS format
images (after appropriate bias, dark, and flat field processing)
into Red (R), Green (V), Blue (B), and Infrared (I) or black &
white grayscale Tiff images in Mira (Axiom Research), MaxIm DL/CCD, or
CCDSoft.
For color imaging, the R, V, B, and, in some cases the I,
grayscale images were then combined in Adobe PhotoShop to produce color Tiff and JPEG images.
The R, V, B, and I filters are STANDARD
JOHNSON-COUSINS PHOTOMETRIC FILTERS. Therefore, there is
no need to worry
about infrared leakage through the filters. Moreover, the
separate R, V, B, and I images contain potential valuable
professional photometric data. All raw
data is saved, giving the Observatory's images potential for later scientific study.
In
March 2001, a
Finger Lakes Instrumentation Dream Machine CCD camera was
installed. This camera had a high quantum
efficiency SITe 1024 x 1024 twenty-four micron CCD chip. The AP7 with a 512 x 512 twenty-four micron chip gave a field of view of
14 arc minutes, while the Dream Machine
provided a nearly 28 arc minute field of view. The Dream Machine was used in operation with a Finger Lakes Instrumentation CFW-1
Color Filter Wheel and an
Optec TCF
temperature compensating focuser. The filter wheel contained
photometric R, V, and B filters and also had an Open slot (O) which later contained a clear (C) infrared blocking filter parfocal with the other filters.
In late 2007 a Quantum
Scientific Imaging (QSI) 532 CCD was acquired with an LRGB
filter set as well as a hydrogen alpha filter all residing in
the QSI 532 internal color wheel. The QSI 532 CCD has a
Kodak KAF-3200ME 2184 x 1472 chip with 6.8 micron pixels.
This camera can gave very high resolution images with the
24-inch f/5 telescope, but guiding was uneven with the original 24-inch telescope. Two x two binning was often used for imaging with the QSI 532 24-inch f/5 telescope combination.
At the present time, the QSI 532 is now attached to an Explore Scientific 102 mm f/7 refractor piggy mounted on the AstroPhysics 1600 mount used to carry a Takahashi Epsilon 180 f/2.8 telescope which resides in its own remotely controlled 14 x 14 foot roll-off roof building. The ES-102 mm refractor and QSI are mainly used for guiding.
The majority of the older images still present on the Grasslands Observatory website were obtained with the Dream Machine
combined with the Finger Lakes CFW-1 Color Filter Wheel using
the photometric R, V, and B filters as well as a clear (C) parfocal filter.
At the present time all imaging is done remotely using the PlaneWave CDK24 24-inch f/6.5 telescope and FLI Proline 9000 CCD, the ASA 20-inch f/3.5 astrograph and FLI Proline 9000 CCD, or a Takahasi Epsilon 180 f/2.8 telescope with a Canon EOS Ra camera.
For several years an 8-inch f/4 Meade LXD75 Schmidt-Newtonian telescope has been mounted onto the side
of the original 24-inch f/5 telescope. Imaging through the 8-inch telescope
is sometimes done on-site with a Canon 20Da or 60Da digital camera back, or the QSI 532 CCD camera.
Almost all of the images on this website are displayed with the north to the top
and east to the left, standard astronomical orientation. This is to provide consistency in image display and orientation from object to object and from year to year.
tbh 27 April 2014; revised Tuesday 9 May 2017; revised Monday 12 March 2018; revised Tuesday 14 May 2019; revised Wednesday 28 October 2020.
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