info and idea request for PI CCDs

[user 1156]

Dear colleagues:
     I bought a LN/CCD 1752PB from Princeton Instruments which is a thinned, 
back illuminated and pixel size 15um, 1752X532 spectrometric detector. I don't
know why its full well capacity is only 5900 e and readout noise 8.6 e. PI 
response me it's the correct CCD. I am curioused if anyone got a better one 
from PI for the ad. I saw before I bought says the FWC not less than 260,000 e
and readout noise 4-6 e (only it's an ad. titled with 'preliminary').
     I got trouble too when I use LN/CCD 1024TKB also from PI. When
it works under -100C, water vapor comes up on the quartz window ahead of CCD 
chip and behind of the shutter (the vacuum condition of the space between the 
chip and the window is good) as the exposure time reaches several tens of 
seconds (the enviomental humidity about 60% and temperature 10C to 15C). The 
lower the working temperature, the quiker vapor comes up. when I uninstalled 
the shutter (there's another quartz window in front of shutter) with the outer 
window together, the vapor no longer came. I cannot do without the shutter in 
my future work. So, I need your help if you can give some ideas to solve this
problem. Consult me with the address:
                     ynaogh at public.bta.net.cn
     Many thanx.
 
Qian Song.