Canon 7D test report: measurement results

The measurements were carried out using Imatest. For the test method and explanation of terms, see the FAQ section. Conclusion and sample images are shown in the test of the Canon 7D.

Resolution of the sensor

The Canon 7D, combined with the Canon 60 mm macro lens, provides an in-camera jpg file with a resolution of about 1500 LW/PH. That is 16% lower than the measured values for the Canon 5D MK2.

With a standard processing of RAW files in Lightroom, the Canon 7D measures the same average resolution (1500 LW/PH) as the jpg files, while the Canon 5D MK2 files yield a resolution of 3000 LW/PH at the same processing in Lightroom. Compared to the Canon 60D, the Canon 7D scores slightly higher in terms of resolution with jpg files in our test, but slightly lower than the Canon 60D with RAW files. Overall, they are equal to each other in terms of resolution.

Dynamic range of the sensor

We have measured the dynamic range with the Auto Lighting Optimizer turned off. The total dynamic range of the Canon 7D sensor measured with Imatest is averaging nearly 12.5 stops for RAW files and 10.5 stops for jpg files. More important than the total dynamic range is the usable dynamic range. The signal/noise ratio determinex what remains of the dynamic range for a displayable image. The usable dynamic range of the Canon 7D is almost 8 stops at the lowest ISO settings and goes down to 0 stops for an unprocessed ISO 12,800 RAW file.

A poor signal/noise ratio in the shadow reduces the dynamic range of jpg files to a seemingly better setting than the RAW files. Yet that is not the case. We test the RAW files without using noise reduction. As such, you maintain the highest possible detail of the images, while the noise (although measurable) is not visible in a print. You can also compare the performance of different sensors easier when you apply no noise reduction in all cases.

If you carefully optimize contrast, sharpening and noise reduction of RAW files, you will get a usable dynamic range for RAW files that is better or equal to that of the jpg files. Below is an example of an edited RAW file in Lightroom, where the usable dynamic range is 8.1 stops. This measured value agrees well with the dynamic range (8,18 stops usable dynamic range) that is measured in the Canon 7D review by Imaging Resource. Imaging Resource always measures the dynamic range of processed RAW files.

Noise

Comparison of the noise in jpg files with the measured noise in RAW files without noise reduction shows that noise reduction occurs at jpg files at all ISO settings. We know from experience that if the noise is less than 2.5%, a photo can be printed on A3 + size without the noise being seen as disturbing.

Today, the noise of SLR cameras is so low that you cannot see noise with the naked eye anymore up to 800 ISO. That is why we no longer show examples of our grey card shot at low ISO. Below are examples of a gray card photographed at a variety of high ISO settings. On the left is the noise of jpg files. On the right from RAW files without any noise reduction. These image croppings show a detail like you would show your photo full size on your screen. By applying noise reduction, an even better achievement can be acquired for RAW files.

Color reproduction daylight

Color reproduction (Delta E 94) Canon 7D in daylight

• Average 5.0 (RAW) / 6.4 (jpg)

• Best 4.7 RAW @ 6400 ISO

• Worst 7.5 jpg @ 3200 ISO

• Skin tone: 5.7 (RAW) / 6.0 (jpg)

• Natural colors: 3.3 (RAW) / 6.9 (jpg)

• Bright colors: 4.7 (RAW) / 7.5 (jpg)

• White balance: 3.0 (RAW) / 3.1 (jpg)

The Canon 7D delivers RAW files with excellent color reproduction and white balance in daylight. We have tested jpg files in the Picture Style “Faithful” and the RAW files with the standard Adobe profile. The Canon showed the most accurate color reproduction of all the cameras that we have tested so far. The red colors are a bit too saturated, but we experience that as pleasant. Frankly, we should add that the differences concerning this point are very small. The measured saturation of RAW files is 118% and of jpg files 92%. In the picture above, you can see the color errors of an ISO 200 jpg image shot in daylight. The further the ideal color (square) is removed from the color of the camera (round), the greater the color difference. For the test method and explanation of terms, see the FAQ section.

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Color reproduction artificial light

Color reproduction (Delta E 94) in artificial light

• Average 11.1 (RAW) / 10.2 (jpg)

• Best 9.1 jpg @ 6400 ISO

• Worst 11.4 RAW @ 25600 ISO

• Skin tone: 11.8 (RAW) / 9.2 (jpg)

• Natural colors: 9.8 (RAW) / 9.6 (jpg)

• Bright colors: 8.7 (RAW) / 9.7 (jpg)

• White balance: 15.2 (RAW) / 8.4 (jpg)

The automatic white balance of the Canon 7D works reasonably. The results agree well with the color reproduction in artificial light of the Canon 60D. There is an orange color cast, but that can be corrected well afterwards. See for example the review of the Sony A77, in which the effect of adjusting the white balance afterwards on the accuracy of color reproduction is demonstrated.

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Read more about our practical experiences in the Canon 7D review.