Quote:
Originally Posted by zoetmb 
It is a bad thing. Higher pixel density means more photosites. More photosites in close proximity generate more heat. More heat generates noise, especially at high ISOs.
Even large sensor pro cameras have faced this challenge: DSLRs from Nikon, Canon, Olympus, Sony and Leica all have had to make compromises in this regard. The Nikon D3x, which is their top of the line body at 24.5MP ($7600 street price) actually gets inferior high-ISO performance than the D3s 12.1MP body ($5200 street), which is why the D3x is intended more as a sports (in bright light) and studio camera and the D3s is intended more as a street and photojournalist camera. While new models have continued to bring better performance in this regard, until someone makes a radical breakthrough in sensor design, this will continue to be the case.
And I don't know how big the sensor in an iPhone is, but I suspect it's smaller than the smallest of the point & shoots. The smallest sensor in P&S cameras is generally 1/2.5" (.4"), but I suspect the iPhone sensor is far smaller. It's amazing it works as well as it does. A 1/2.5" sensor has only 2.9% of the area of a 35mm-sized sensor and about 6.6% the area of a typical APS-sized sensor.

It is a bad thing. Higher pixel density means more photosites. More photosites in close proximity generate more heat. More heat generates noise, especially at high ISOs.
Even large sensor pro cameras have faced this challenge: DSLRs from Nikon, Canon, Olympus, Sony and Leica all have had to make compromises in this regard. The Nikon D3x, which is their top of the line body at 24.5MP ($7600 street price) actually gets inferior high-ISO performance than the D3s 12.1MP body ($5200 street), which is why the D3x is intended more as a sports (in bright light) and studio camera and the D3s is intended more as a street and photojournalist camera. While new models have continued to bring better performance in this regard, until someone makes a radical breakthrough in sensor design, this will continue to be the case.
And I don't know how big the sensor in an iPhone is, but I suspect it's smaller than the smallest of the point & shoots. The smallest sensor in P&S cameras is generally 1/2.5" (.4"), but I suspect the iPhone sensor is far smaller. It's amazing it works as well as it does. A 1/2.5" sensor has only 2.9% of the area of a 35mm-sized sensor and about 6.6% the area of a typical APS-sized sensor.
I can't totally agree here. The D3X has superb image quality, and is used in the studio, for fashion and other high quality work. It has excellent s/n for a 35mm size sensor camera. While the D3s has slightly better s/n, in the same size, fairly large print size, it loses out, and quite noticeably. So in that I can agree, but as far as street photography goes, unless we're talking about night photography, the D3x will still give better IQ. I know of no photographers who need to shoot above about 3200 ISO, unless they're just trying to capture an image without the highest IQ being important. As the "s" isn't much better at 3200 than the "x" I would still prefer the "x" over the "s".







