Re: ATM amateur infrared imaging?

[Frank Henriquez <frank@ucla.edu>]

Stan,
  IR imaging at 2 microns is probably out of the reach of all but the 
most well-heeled and technically proficient "amateurs".
  The NICMOS III IR array used in the 2MASS survey is around $50K. The 
NICMOS array (and for that matter, all IR arrays) has to be 
cryogenically cooled, typically with liquid nitrogen, or a closed 
cycle cooler. While LN2 is very cheap, you'll need a cryostat with a 
calcium floride, or other IR transparent window, a K or K' filter, 
and a diffusion pump to get a good vacuum. The NICMOS array is 
particularly sensitive to water, and we had to bake ours for up to a 
day to drive all the water out of the array.

Next, you'll have to design the drive electronics and A/D conversion 
circuits, and write the data acquisition software. Luckily, the 
NICMOS III array is easy to drive (it's a CMOS device).

Assuming that you have an excellent machine shop and a diffusion pump 
handy, you're looking at maybe $60K - $75K (or higher) so the dewar, 
detector and electronics.

If you want to do near IR imaging, the easiest way to do it is with a 
CCD camera and an I filter (from the UBVRI set) or a similar IR pass 
filter.

I used this setup on a 24" telescope to make a color image of M42, 
using the VRI filters. The results were impressive, since the I image 
could see through much of the dust at the heart of M42, revealing the 
rest of the cluster.

Frank
-- 
Frank Henriquez  Programmer/Analyst  Jules Stein Eye Institute, UCLA
frank@ucla.edu   http://www.bol.ucla.edu/~frank/index.htm