View Single Post
  #8  
Old 17-06-2009, 08:28 AM
Geoff45's Avatar
Geoff45 (Geoff)
PI rules

Geoff45 is offline
 
Join Date: Jul 2006
Location: Sydney
Posts: 2,438
Quote:
Originally Posted by Bassnut View Post
Well, QE on a DSLR is typically 15%, a CCD at least 35% (for a big chip) and over 50% (up to 80% peak) for a smaller one. well depth for a 40D is 25K (I think), a CCD is often 100K, noise is always much lower in a cooled CCD. Dynamic range on a 350D is 12 bit (14bit on a 40D), astro CCDs are 16 bit.

A single shot colour CCD is better than a DSLR, given the cooling and 16bit A/D convertor.
DSLRs do better than this. Typically 40% in the green. See the attachment from the sbig site. Their weaknesses are no cooling, nosier, 12 or 14 bit and low QE in the H alpha region
Attached Thumbnails
Click for full-size image (4020_dslr_qe_spect.gif)
14.5 KB23 views
Reply With Quote