Image Sensor, Dynamic Range and AF Performance
The Canon 7D Mark II sports a 20.2 MP APS-C sensor (1.6x crop factor), with a native ISO sensitivity of 100-16,000, which can be pushed further up to ISO 51,200. Unlike Nikon, which often buys sensors from other manufacturers like Sony and Aptina, Canon develops and manufactures its own sensor technology for its cameras. Although the 20.2 MP APS-C sensor sounds a lot like the sensor from the 70D, Canon claims that the sensor technology was not reused in the 7D Mark II and that the sensor was newly developed for the camera. While I have not compared the two cameras side by side to see what differences there are in performance, folks at DxOMark performed their analysis of both cameras and here is their conclusion on high ISO performance and dynamic range:
Indeed, it seems like Canon has made changes to the sensor on the 7D Mark II since both noise / SNR and dynamic range appear to be a bit different. However, it is important to note that the changes are not drastic and only appear to be noticeable at higher ISOs, particularly in regards to SNR. What’s particularly disappointing is how little the change is in dynamic range. As you can see from the graph above, there is practically no difference at ISO 100 and at other ISO levels, dynamic range improvements do not exceed half a stop. To understand how far Canon is behind its main rival Nikon, let’s go ahead and add the Nikon D7100 to the mix:
Now, this right here is the reason why Canon gets so much heat for its proprietary sensor technology. Look at how far up the Nikon D7100 is at lower ISO levels, reaching close to 14 stops of dynamic range, while the 7D Mark II struggles to reach 12. If you do not believe in numbers, see my post comparing Canon and Nikon in Dynamic Range, where I show how much worse Canon is in both overexposing and underexposing images.
And here is a summary of the comparison of the 7D Mark II to the 70D and Nikon D7100:
Based on what DxOMark shows, the 7D Mark II’s sensor is inferior to the sensor on the Nikon D7100 in every way, from the color depth and dynamic range to high ISO performance. However, do not be confused with the low-light ISO scores above – having a score of 1082 compared to 1256 does not represent 16% inferior performance. DxOMark claims that a difference of 25% represents only 1/3 of a stop difference, so the 7D Mark II is not significantly worse in handling noise when compared to the D7100. In fact, as you will see from the camera comparisons page of this review, the 7D Mark II performs similarly at high ISOs and there is little difference between noise levels on the two cameras.
Overall, although the 7D Mark II does quite well in handling noise, its dynamic range performance is rather disappointing when compared to other modern APS-C sensors.
Although it might seem like the 7D Mark II might have the same autofocus system as on the 5D Mark III and 1D X cameras, the Canon 7D Mark II actually has a newly developed AF system that is better than all other current Canon DSLR cameras, including the top-of-the-line EOS-1D X. First of all, there are 65 focus points available, all of which are cross-type, compared to 61 focus points, 41 of which are cross-type on the 5D Mark III and 1D X. Here is a comparison of the viewfinders between the 7D Mark II with the 1D X:
In contrast, the Nikon D7100 has 51 focus points and only 15 of them are cross-type. As explained in my autofocus explained article, cross-type focus points are much more accurate when compared to regular/one-dimensional ones, so having that much precision in every single focus point helps a great deal in obtaining more in-focus images when using different focus points. With the 7D Mark II, the flexibility to pick any of the focus points without worrying too much about potential focus errors is a great relief when shooting any kind of subject.
On top of this, the 7D Mark II has a low-light sensitivity rating of -3 EV and it is a more suitable tool to be used with teleconverters (focuses at up to f/8 range with the center focus point). Both the 5D Mark III and the 1D X are rated at -2 EV.
Where the 7D Mark II is inferior when compared to 5D Mark III and 1D X is high-precision dual cross-type AF points: the 7D Mark II only has one of those, while the other two cameras have 5 of them. Please note that only some of the latest generation Canon lenses with apertures of f/2.8 or faster are able to take advantage of these dual cross-type AF points, so it is not necessarily an advantage when using older glass and slower lenses.
But all these numbers can be just numbers if the AF system is unreliable. I have been shooting with the latest Nikon DSLRs like the Nikon D750 with Advanced Multi-CAM 3500FX system and I love the reliability of the autofocus system. It is both fast and accurate, especially when shooting in low-light conditions. When assessing the autofocus performance of the 7D Mark II, I wanted to get a feel for how it compares to the Nikon AF system and compare the two, as objectively as possible.
When shooting with the two AF systems side by side, I found the 65-point autofocus system on the 7D Mark II to be very strong when compared to Nikon’s Advanced Multi-CAM 3500DX / FX. The main advantage is the all cross-type AF system. Where Nikon can struggle at obtaining focus outside the central focus area in Single Servo / AF-S mode, the 7D Mark II just nails focus pretty much every time, making it a more versatile setup when using outer focus points for everyday photography. For shooting fast action in AI Servo / AF-C mode, both systems have their pros and cons and it is hard to say which one is a clear winner.
Shooting the 7D Mark II using AF Point Expansion with 9 points gave me pretty similar results to what I typically get with Nikon’s 9-point dynamic AF. The hit ratio was very good and the number of keepers was high. Sadly, Canon does not have the ability to pick more focus points for its dynamic focusing, so I could not compare performance with more focus points. I did not do a lot of testing with Canon’s intelligent Tracking and Recognition (iTR), as I do not like to let my camera pick what to focus on. From what I gather, it works similarly as Nikon’s 3D autofocus mode.
What I liked about the Canon 7D Mark II focus system is its fine-tuning options. Nikon cameras usually have only one setting that allows fine-tuning AF and it is called “Focus tracking with lock-on”. Basically, this setting allows you to specify how long the camera will wait before adjusting the focus on a subject – you can specify short to long values, depending on what you are photographing. In comparison, the Canon 7D Mark II has three configuration settings: “Tracking sensitivity”, “Acceleration/deceleration tracking” and “AF point auto switching”. By using different combinations of these settings, one can really adapt the AF system to practically any situation. Canon even provides “cases” or templates that are basically different combinations of these three settings:
Overall, the autofocus system on the 7D Mark II is very solid and deserves high praise for its performance. Let’s now take a look at the buffer capacity of the camera and compare it to the Nikon D7100.
The Canon 7D Mark II has an impressive continuous shooting speed of 10 fps, but how good is fast shooting speed if a camera does not have a big enough of a buffer to accommodate all those images? Let’s take a look at the buffer capacity of the Canon 7D Mark II and compare it to both its predecessor and the Nikon D7100:
|Camera Feature||Canon 7D Mark II||Canon 7D||Nikon D7100|
|Continuous Shooting Speed||10.0||8.0||6.0|
|Continuous Shooting Duration (RAW)||3.1 sec||3.1 sec||1.5 sec|
It is pretty clear that the Canon 7D Mark II is way ahead of the other two cameras in both continuous shooting speed and buffer capacity. But how does 10 fps really compare to say 6 fps and how does the buffer capacity impact the continuous shooting duration? To answer these questions, I shot a video where I demonstrate the difference between the 7D Mark II and the Nikon D7100:
Without a doubt, the Canon 7D Mark II is a much better choice for photographing fast action than the Nikon D7100…
In addition to the brand new autofocus system, Canon also bundled a brand new metering system with a 150,000 pixel RGB and IR sensor, which puts the 7D Mark II ahead of both 5D Mark III and 1D X, which have older metering systems. The new metering system is capable of recognizing 252 zones and it is also capable of reading full color, which results in superior exposure metering performance. When photographing different scenes in varying lighting conditions, I found the metering sensor to be fairly accurate when shooting in Aperture Priority mode. All metering modes (evaluative, center-weighted, partial and spot metering) worked as expected and when I did have exposure problems in some rare situations, taking care of the exposure issues with the 3-step exposure compensation using the big rotary dial on the back of the camera was pretty easy.
As for battery life, the Canon 7D Mark II is rated a bit below its predecessor at 670 shots versus 800, most likely due to more demanding processing requirements for handling so much more data. With a dual-processor architecture, more advanced AF and metering systems, it is expected that the camera will yield fewer shots per charge. However, keep in mind that these figures are CIPA estimates that take into account flash, live view and image preview use.
If you do not use flash, sparingly use live view and turn off image preview, you should be able to yield over 1000 images per battery charge. Make sure to turn off GPS when you don’t need it, as it will eat up the battery pretty quickly. Also, keep in mind that the battery performance degrades when temperatures are very low. The battery indicators on the top LCD and in the camera menu seem to be pretty accurate, so it should be a pretty good indicator of both charge potential and battery health.
Canon’s implementation of Live View is excellent. No interpolation at 100% zoom and superb clarity at all zoom levels. I love the way Canon designed the Live View/Movie switch with the Start/Stop button that changes in functionality depending on whether you are in movie or live view mode. Changing the switch to video mode automatically flips the mirror up and starts the video mode and the Star/Stop button is used for recording video. This is a great feature for videographers since you can keep the setting on movie mode when powering the camera on or off and the mirror will automatically lift up or down without the need to press anything.
Although there is still no 4K video support, the 7D Mark II has superb HD movie recording capabilities, allowing up to 60 fps at a full HD resolution of 1920×1080. Canon obviously does not want its DSLR line to compete with high-end dedicated video recording cameras like the EOS 1D C, which is why there are some limitations. Personally, I look at video recording as a “nice to have”, since I rarely ever shoot video…
The GPS capability also works quite well, which is a huge plus for travel and landscape photographers. The camera obviously needs a clear sky to locate satellites initially, but once it is done, the tracking works quite well when traveling. I experimented with the GPS feature a few times and it seemed to track location fairly well. However, I had GPS mostly turned off when traveling in California, since I only had a single battery and wanted to preserve battery life as much as possible.
Setting up GPS is easy. Locate the “GPS/digital compass settings” option in the camera menu under the wrench menu, then set GPS to “Enable”. Next, go to Set Up and set other options. I set up “Auto time setting” to “Enable”, “Position update intvl” to “Every min”, enabled “Digital compass” (I recommended to calibrate the compass after enabling it) and disabled GPS logging. Keep in mind that updating of position frequently drains battery fairly quickly, so if you want to save power, set “Position update timing” to a longer interval.
See the next page to see more examples of Canon 7D Mark II’s ISO performance, along with comparisons to Nikon D7100 on the following page.
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