Light Detectors used in Astronomical Image Making

 
eye
photograph
photo-
multiplier
CCD
quantum
efficiency
1% max,
sharply
peaked 
at 550 nm
1%,
fairly uniform across visible
10-20%,
peaks 
toward uv
70-90%,
peaks
toward ir
photometric
response
logarthmic
non-linear
linear
linear
dynamic range
(Imax/Imin)
1010
but only 
100 at a time
< 100
<100
1000-
10,000
geometric
stability
 
good
fair
exceptional