[pjphilli (Peter)]

Hi
Having previously used a modified Canon 400D for astro imaging I have recently used a QHY8 CCD colour camera.
I soon noticed that the QHY8 camera is considerably more sensitive (ie
less exposure time required) than the 400D. I see that the 400D CMOS pixels are 5.7microm square whereas the QHY8 CCD pixels are 7.8microm square, ie about twice the area of the CMOS. So I guess this would account for the QHY8 having at least twice the sensitivity of the 400D.
However, I have seen suggestions that for a equal size pixel that CCD is
more sensitive than CMOS. I have looked back on previous threads but got lost in the talk about "quantum efficiency". Could someone put this in terms of a simple fraction?
Cheers Peter