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Grasslands Observatory Image Gallery


Coma Cluster (Abel 1656; NGC4889)
Coma Cluster
Black & White
 
Coma Cluster
Color


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 resides on a TPO RC 16-inch f/8 telescope in its own remotely controlled 14 x 14 foot roll-off roof building.

The majority of the images presently 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 Grasslands imaging is done remotely using a PlaneWave CDK24 24-inch f/6.5 telescope and FLI Proline 9000 CCD or the TPO RC 16-inch f/8 telescope and the QSI 532 CCD. Either on-site or remote imaging a Takahashi Epsilon 180 f/2.8 telescope and a Canon 60Da camera is also sometimes done.

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
 

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