Quote:
Originally Posted by gregbradley
Thanks for answering my questions Ray. As always you provide some interesting insights and makes even happier with the F3.8 system.
By the way I think some DSLRs are probably up around 65% QE. CMOS sensors in digital cameras are getting all the research. Take a look at the about to hit the market Sony A7r - backside illuminated full frame 42.4 mp sensor with copper wiring rather than aluminium and 3.5X throughput as a result. So higher QE than A7r which is currently rated around 60% QE. I believe it as a 30 second ISO6400 image at F2.8 lights up everything.
Greg.
|
Hi again. Modern sensors could have a peak QE of 65%, but the sensitivity calculation outlined above is based on average QE - the Bayer filter absorbs about 2/3 of the photons that hit it (just doing it's job), so it is not possible for a Bayer chip to have anything much more than about 30% average QE. It suits camera makers to quote peak QE, because it looks better, but Bayer chips actually take a huge hit in average (true) QE.