If you find new defects, please report them to Michael Richmond via E-mail to mwrsps at rit dot edu
There are several locations on HDI where foreign material appears to have stuck to the surface of the detector. The pixels near these locations may not be corrected adequately by the standard reduction steps (subtracting overscan, flatfielding), and therefore observers should try to avoid placing their targets near them.
One of the defects is, unfortunately, near the center of the chip.
The most prominent defects are located in the regions marked with letters in the chart below. Note the orientation of the image: it matches the orientation of the "quick look" images in the HDI web browser window.
Each of these defects results in pixels which contain less light than their neighbors. It is a big easier to see them in a large scale if one reverses the color map.
The pixel locations of these defects, using the convention of DS9
(0, 0) in the south-west corner of the chip
X increases from West to East
Y increases from South to North
are as follows:
label X Y description
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A 1982 2153 "hair" near center
B 425 1800 "saturn" near West edge
C 292 881 "kidney" near SW corner
D 260 3220 "puppet" near NW corner
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A closeup of each defect follows. Each cutout is 300 x 300 pixels, with orientation North up, East left (the same as the earlier charts in this document).
Defect A:
Defect B:
Defect C:
Defect D:
