Noise (8.61)
For digital cameras, we test image noise at two light levels across various ISO settings. Unfortunately, on the iPhone, you have no manual control over the ISO, so we had to use the default. The iPhone 3G S is the first iPhone to include proper EXIF data, so for the first time we can see what ISO it was shooting at, which is something of an improvement at least. Under our 60 lux setup, the phone shot at ISO 561, and under 3000 lux it shot ISO 144. In the former, the noise levels were 2.15% and the latter was 1.39%. Compared to a camera, this is a bit high, but not too bad for a phone. Click here for more on how we test noise.
This chart shows the noise under the two light levels.
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Auto ISO |
| 60 Lux |
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| 3000 Lux |
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Compared to the other iPhones, the 3G S is an improvement over the 3G but worse than the first generation. It has a better score than the Sony T900 because the Sony's score takes into account higher ISO levels, all the way up to ISO 1600.
| Noise Score Comparison |
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ISO (6.00)
While there is no manual control over the ISO, we photographed with the 3G S in bright direct light, and in pitch black, in order to figure out the range of ISOs it would use. The lowest we could squeeze from it was ISO 70, the highest ISO 1016.
The chart below shows a 100% crop of our still life setup. Usually we show it across all the ISOs, but due to the lack of control on the iPhones, we can only show the one. The iPhone 3G S EXIF data tells us that it shot at ISO 72. The other two iPhones don't attach EXIF data properly, so we must work on the assumption that they shot at a similar level. The Sony T900's lowest ISO level is 80, and we're using that for comparison.
NOTE: The images above are not used in our testing or scoring, but are included here to show real-world examples of the differences between cameras at the various ISO settings.
