Canon EOS 7D Review / Test Report - Sensor Noise
DSLR Reviews - DSLRs
Friday, 29 January 2010 00:00

ISO noise

Let's have a look at the results of Canons' 22.3x14.9mm C-MOS sensor with respect to the ISO performance.

Based on converted RAW filest the EOS 7D is generally a good performer throughout the ISO range. There are no problems at ISO 100/200 and ISO 400 and ISO 800 are also perfectly fine for most scenes. However, at ISO 1600 and more so at ISO 3200 the noise level is starting to have a higher impact but they may be still usable at times. ISO 6400 is a setting "non grata" (=senseless) unless image quality is a non-issue (we've spared you the numbers for this one). Here's the corresponding chart:

Now what about the JPEG results...

First - JPEGs with disabled noise reduction ...

The results are pretty much in line with the RAW results. At very high ISO settings the results start to smoothen - probably a side effect of the JPEG algorithm.

Here's the corresponding chart for the results based on "standard" noise reduction:

You may notice that the curve looks drastically different. However, this is only part of the truth. The noise reduction algorithm introduces artifacts such as blotchiness in conjunction with a reduced resolution as we've seen in the previous chapter.

In order to visualize the performance - here're some 100% crops (converted RAWs) taken from a color test chart:

Note: the slight variations in color temperature were caused by the camera - the white balance was fixed at the time.


low ISO noise (ISO 100-200):
mid ISO noise (ISO 400-800):
high ISO noise (ISO 1600-3200):