I was doing some research this morning about low light photography and image noise. A few minutes into my research I found a few interesting articles discussing how CCD Sensors are less noisy than CMOS Sensors commonly found in today's DSLR's. That made me question, "Why are CCD sensors not used in DSLR's?".
With this hole PIPA / SOPA fiasco going on of course Wikipedia was offline so I had to look for other sources of information. I happened to stumble upon an article that satisfied my question which happens to be linked below. A few things surprised me. The first being how the Canon 5D ranked the highest regarding nose handling performance.
I use to own and absolutely loved the Canon 5D. Unfortunately I sold it to upgrade a few years back. One of the first things I noticed after the upgrade was that the chip in my newer camera while awesome just did produce images like the 5D. The images produced by the 5D were something else. I'm not exactly sure what it is was but they had a degree of warmth and feeling to them that my newer sensor lacked. Comparing the images produced by the 5D to the images of my newer DSLR side by side proved my suspicion. This might be part of the reason why. A part of me wishes I never sold that camera.
The main reason for selling the Canon 5D was sensor dust! No matter how careful I was, no matter how often I cleaned, sensor dust was always an issue and caused numerous headaches during post processing. I ended up having to clean the sensor before every shooting opportunity and I was spending a small fortune on sensor swabs and cleaning fluid. With my newer DSLR I rarely clean the sensor but now I deal with higher degrees of noise. I've learned to overcome the issue by making sure exposure is spot on and while image quality is fantastic, its just not the same. =)
I also learned that while CCD's back in the day did have better noise performance, CMOS sensors with today's manufacturing processes are are just as capable. Noise performance from CMOS sensors is just as good within reasonable operating conditions. The article went a step further by taking into account CCD Sensor backs by Hasselblad, LEAF, and PHASE ONE. After testing they claimed that none of those cameras had a distinctly less noisy sensor then other CMOS DSLR's of today. Image quality and dynamic range on the other hand is a different story. =)
I'm happy to see that in recent professional / prosumer offerings by camera manufacturers they are focusing less on megapixel count and more on image quality and low light performance. I could care less about the latest bells and whistles. I want good low light performance which they seem to be working on and higher dynamic range. Hopefully in the near future we will see sensors with more dynamic range hitting the shelf. Check out the article, it's a great read.
DSLR CMOS vs CCD BAYER SENSOR ANALYSIS