View Single Post
  #36  
Old 14-04-2008, 10:24 PM
Peter Ward's Avatar
Peter Ward
Galaxy hitchhiking guide

Peter Ward is offline
 
Join Date: Dec 2007
Location: The Shire
Posts: 8,090
O.K watched this thread with interest. Can anyone explain how a HAD sensor and differentiate a thermally liberated electron from one freed by a photon?

My understanding on this is: you can't.

A high QE sensor is rather like a high power amplifier. Crank it up and you'll hear a "hum". HAD sensors bleed charge all the time...O.K. low noise...but the signal is being bled as well.... in short they never really hum as the gain is being suppressed.

Yes, it does take some work to separate the signal from dark current in various sensors, but the results are worth it.
Reply With Quote