Quote:
Originally Posted by sjastro
I have done NIR imaging using a ST-X10ME which has QE of around 65% at 0.75 microns and drops to around 30% at 0.9 microns.
Recently I tried a test image of the emission nebula RCW71 which is located behind the Coalsack in near infrared but found the results disappointing.
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Steven,
Your experiment with NIR imaging is interesting.
Even though I am currently writing an article about the Coalsack, I haven't actually considered the case of RCW 71. (though I have seen this nebula on various images.)
It seems to me that you are right that the nebular emission being mainly output at a few specific spectral lines (mainly OIII and H-alpha) might be a reason for there being little signal at near-infrared wavelengths.
Abell (ACO) 3627, the rich but obscured cluster of galaxies in Triangulum Australe, could be an interesting test object for NIR imaging, as the member galaxies will have plenty of emission at red and infrared wavelengths
(note: I ran a thread recently as to why this cluster is referred to, even by professional astronomers, as the Norma Cluster)
cheers,
Robert
Here are a couple of links relevant to 700nm - 1000nm sensitive CCDs:
http://www-ccd.lbl.gov
http://snap.lbl.gov/ccdweb/ccdpapers.html
(several papers about CCDs with extended infrared sensitivity)
The book "Optics in Astrophysics", (2005), by Foy and Foy, contains a section on how CCDs are optimized for various wavelengths. Some of it is available at Google Books