Keith_Reeder said:
Don Haines said:
and if the 6D2 is fewer megapixels than the 5D4, that also helps for low light performance...
But that doesn't happen, does it? Look at the entire 5D series - pixel count
and low light performance have increased/improved with each model.
Same with the xxD series.
My first DSLR maxed out at ISO 1600 and was unusable after 400..... yes, they have been steadily improving over time and now that we are hitting 70% and higher quantum efficiency on sensors, we only have a half stop left to go on the efficiency side of the equation...... the latest designs put the A/D on chip and as a result, the amount of read noise has plummeted....
As a result, even with shrinking pixel size over the years as we climbed from 6 to 30 (or more) megapixels, we got better and better quality pixels. Short of cooling the sensor, there is no significant source of noise left and one should not expect improvements of more than a few percent as new models come out..... That leaves pixel size as the big variable....
Take two FF sensors made with the same technology..... one at 25MP and the other at 50.... we can say that the same amount of light falls on each sensor and that therefore, after resampling both images to the same size, the low light performance should be the same, and we would be close to being right. Unfortunately, pixels have waste area around the edges and so does your Bayer filter and your micro lenses... as a result, the larger pixel sensor uses a greater percentage of the sensor area to gather light and therefore gives you a stronger signal. The lower amount of circuitry should result in less thermal noise, and therefore give a cleaner signal.
All that said, we are NOT using the same technology. Lessons learned from one sensor are implemented on the next and each new design is slightly better than the last. When the 6D2 comes out we can expect it to have the best Canon sensor (until the next camera is released), and with all of these variables included, we can reasonably expect it to be Canon's low light king....