Quote:
Originally Posted by parejkoj
Huh. Here's the object in Google Sky. I can definitely see why you wanted a spectrum of that! That's exactly the sort of thing I was wondering about. A very good alignment there.
What kind of imager was used to get that picture? The weird row artifact doesn't look like a typical CCD problem. |
A TI 800x800 CCD at CTIO. I've used a couple of systems (on at Lowell for a while also did this) in which there was some kind of depression of the bias level when the total row intensity was too high (there are median tricks that can get rid of it pretty effectively). From that same run in 1988, I have some images of SN 1987A and its early light echos which show the same thing (just to make it harder to put together a pretty color composite - or even an acceptable color composite). From that date, you might guess that I'm slightly compulsive about archiving my own data.
By the way - both Skyview and Google Sky use the same sampling of the old SERC J survey plates. The diffraction spikes are a bit narrow to show up well in that, one of the details downplayed by the digitized versions.