Canon EOS 7D Review

Since August 2010 (so now for 2 months), I have owned the Canon EOS 7D. Slowly but surely, I've come to understand the pros and cons of this megapixel powerhouse as it stands at this time. I'd like to share these insights with you.
First, let's begin with a few figures. With 18 MP, the camera has a very high resolution for an APS-C camera. Consequently, the pixel density is around 5.4 MP/cm², which is about as high as with current Four Thirds cameras (as of October 2010), such as the Olympus E-5 with 5.1 MP/cm², even though it has a resolution of only 12.3 MP. This pixel density does come with some drawbacks, which I'll discuss later. The Canon EOS 7D has 19 cross-type AF sensors and various AF modes in which these sensors work together in different groups. This offers advantages, especially for moving subjects, which I'll explain later. In addition, you can achieve pinpoint focus using the Individual Functions menu with a SPOT AF feature. I'll come back to this feature, as well as the fantastic LIVE VIEW mode with highly accurate contrast AF.
For me, the most interesting feature was the built-in flash, which allows you to control additional external Canon flashes wirelessly through the camera menu. This eliminates the need to carry at least two external flashes on photo shoots or the need to purchase a transmitter for wireless operation.
Now let's get down to business. There is an abundance of spec sheets available on the internet. Let's dive into practical testing of the camera because it's not the numbers that matter but rather the image results that the camera can or cannot deliver. Keep in mind throughout this review that it is entirely based on my subjective experiences.
Let's begin with the autofocus:


AF Performance of the Canon EOS 7D

The autofocus system of the Canon EOS 7D uses 19 cross-type sensors. In contrast, my previous model, the Canon EOS 40D, had only 9 autofocus points. I find that the autofocus points are somewhat centered, which, in my opinion, limits creative framing possibilities for subjects that are not in the center of the frame. When panning the camera, it's easy for the main subject's focus to shift, which can be frustrating for those who are very particular about sharpness, like myself. While I think the distribution of autofocus points could have been better, I must admit that the autofocus performance is significantly improved compared to my previous 'two-digit' Canon DSLRs. It's fast and reliable. Even with my slow EF 180mm/3.5 macro lens, I can still capture images of flying seagulls, as you can see in the photo.

The photo shows a laughing gull in flight with a high-contrast background. This is a challenging situation for cameras because the autofocus (AF) often gets stuck or focuses on the background. The Canon EOS 7D has handled such situations better than my previous two-digit Canon DSLRs.

The Canon EOS 7D offers more flexibility with autofocus compared to previous two-digit Canon models. You can group AF points together, allowing you to use only specific AF points, such as the central ones. This is particularly useful for capturing moving subjects that are challenging to keep within a single AF point. For photographing birds in flight, I found the best results using Servo AF with Zone AF by selecting the central zone. This mode uses the 9 central AF points for focusing and attempts to keep the closest subject sharp, which is beneficial when shooting birds with a busy, high-contrast background.
Similar to Canon's 1-series models, the EOS 7D also provides the option to expand the AF points. This is known as AF Point Expansion. You choose an initial AF point for focusing, and the adjacent AF points assist with maintaining focus on moving subjects. This mode allows for less precise tracking than Single-Point AF, but there's a risk that the AF might inadvertently focus on the background if the subject moves out of the selected AF area.
Additionally, the EOS 7D offers the SPOT-AF mode, which allows you to use only a portion of an AF point. This mode is particularly useful for macro photography or when you need extremely precise focusing on a specific part of the subject, such as the eye.
In summary, I'm generally satisfied with the autofocus capabilities of the Canon EOS 7D, except for the somewhat centralized distribution of AF points. The camera provides multiple AF modes, allowing photographers to adapt to different shooting situations


18 MP and the resulting ISO Noise

Let's now talk about the noise behavior of the Canon EOS 7D. I was aware, even before purchasing, that one shouldn't expect miracles in terms of noise from an 18MP APS-C camera. However, I had hoped that the noise would at least remain within reasonable limits, similar to what I experienced with the Canon 40D in the ISO 100 to 400 range. Unfortunately, the noise, especially in the most frequently used ISO range of 100-400, is noticeably stronger compared to the 40D. The 7D exhibits noticeable noise even at ISO 100, and this becomes particularly apparent when you apply post-sharpening to the images, which are inherently slightly soft. While ISO 400 was easily usable with the Canon EOS 40D, I would no longer recommend it with the 7D, at least not if you intend to sell the images to publishers. I strive to deliver top-quality results, and in my opinion, the ISO 400 images from the 7D no longer meet that standard. So, I try to stay within the ISO 100 to 200 range whenever possible

Photo of my son photographed with ISO 3200. With some post-processing, the results turn out quite decent, and you can even print them up to DINA5 size without any noticeable graininess in the printed image.

When examining images at ISO settings above 400 on the Canon EOS 7D, it's evident that the noise performance becomes more similar to that of the 40D. It reaches a point of parity around ISO 800. Beyond ISO 800, the balance shifts in favor of the 7D. Surprisingly, even at ISO 1600, and occasionally up to ISO 3200, you can still capture reasonably usable shots for small-format prints. It's peculiar with the 7D; while noise performance in the low ISO range may not be satisfying, its quality shines, especially in the 1600/3200 ISO range compared to other cameras. Regarding noise performance evaluation in many camera tests, I'd like to add a few thoughts. In numerous tests, the camera's resolution is downscaled to compare noise performance between two cameras. I can't quite follow this approach. After all, I purchase an 18MP camera to utilize the full 18MP. If I print an 18MP file at 300dpi and a 10MP file at 300dpi, I must compare the two prints. It becomes clear that the 7D exhibits more noise in this scenario.

I captured an image of a Waxwing using my Canon EOS 7D, a 400mm f/2.8 lens, and a 1.4x extender, all at an ISO setting of 1600. While reducing noise in my son's photo was a straightforward process, post-processing the image of the bird turned out to be more challenging due to its fine feather details.

The usability of different ISO settings in photography depends largely on the subject. For instance, ISO 3200 results can be made usable with some post-processing, as seen in the photo of my son. While the Waxwing image looked great on the web, viewing it at its original size revealed significant issues. Noise obscured the fine feather details, making post-processing quite challenging, even for an ISO 1600 image. This was particularly demanding since the image might be intended for sale and needed to have high resolution, rich detail, and minimal noise. To achieve this, I had to downsize the 18MP image to 3000x2000 pixels, which was a laborious task. To compare I resized ISO 400 images from the 7D to match the 40Ds file size, and sharpened the downsized 7D images to roughly match the sharpness of the 40D images. The result revealed that the 7D exhibited visible noise, especially in low ISO settings. This noise was not limited to dark areas but also appeared in mid to moderately bright regions. In summary, the 7D tends to exhibit noticeable noise in low ISO settings, emphasizing the importance of being skilled in post-processing for those who seek perfectly smooth images.


Image Quality

In previous camera models I had complaints about color reproduction, particularly regarding skin tones. However now I'm pleasantly surprised by the color reproduction of the EOS 7D. I find that the color reproduction has improved and is more to my liking, even though it might not match the quality of the Canon D60 or the Canon EOS 10D. Color perception is subjective, and opinions about color reproduction can vary from person to person. Let's take a closer look at the overall image quality. I've noticed that the images from the 7D tend to have a slightly softer appearance compared to, for example, the Canon 40D or 400D. Even with top-quality lenses like the EF 400 2.8 L IS USM or the EF 180 3.5 USM, I don't always see a significant increase in fine details. It seems that the amount of detail doesn't proportionally increase with the image size. My impressions align with findings from various test reports. In my view, the 18-megapixel resolution of the 7D is borderline. One other observation I've made is that the JPEG files straight out of the camera seem to be sharper and more detailed compared to the RAW files, even when the RAW settings are identical to the in-camera settings. I wonder if the JPEGs undergo additional post-processing, possibly involving sharpening or applying an unsharp mask. In the past, I mainly worked with RAW files, but with the 7D, I often find the JPEGs sufficient as long as they are correctly exposed, and the white balance is accurate. I haven't noticed a significant gain in detail from processing the RAW files. Currently, I'm contemplating whether I should partially forego shooting in RAW. It's a common recommendation to preserve RAW files, especially since the capabilities of RAW converters and image editing can significantly improve over time, potentially allowing for better development of images in the future. However, to be honest with myself, I'm unlikely to revisit or reprocess the RAW images I captured with my 10D or 20D in the past.

In mushroom photography it is often necessary to use a small aperture (in this case, f/22) to capture the mushroom cap in sharp focus. The effects of diffraction blurare already quite noticeable in the original image file, but they do not pose a significant issue or distraction.

Returning to the topic of image quality, the Canon 7D doesn't produce the same sharp 'out of the camera' images as the 60D and the 10D, but this wasn't unexpected given the resolution differences. Eventually, one encounters physical limitations. For instance, if you stop down the aperture to a setting smaller than f/10, you'll notice a reduction in detail sharpness due to the effects of diffraction blur. With the 10D, I could easily stop down to f/16, but doing so with the 7D is not advisable. Diffraction blur was present with the 10D as well, but it was within the range of a single pixel, whereas with the 7D, it extends beyond one pixel. If you resize the image to the same size as an identical image from the 10D, you won't perceive any significant difference in this aspect. Bäh---


Conclusion

I'm still uncertain whether I'll find happiness with the Canon 7D or not. When it comes to macro photography using my reliable 180mm macro lens, it excels and delivers impressive results. However, what significantly bothers me is the noise at low ISO settings. Back with the 40D, I could capture fantastic macro shots even at ISO 400, even when the subject exhibited slight movements. However, with the 7D in the macro realm, I feel compelled to use ISO 100 to prevent noise from degrading the image or sacrificing essential details. After all, when you have 18 megapixels at your disposal, you want to maximize their potential for detail, and I 'm not talking about capturing 'noisy details'.
Another aspect that frustrates me is the limited compatibility of my 400mm lens with teleconverters on the 7D. The 2x converter seems nearly unusable with this camera, and the 1.4x extender, while still workable, comes with restrictions. This is disappointing because it now forces me to get closer to my subjects or invest in a larger prime lens. When I encounter suggestions in online forums about simply cropping for a closer view given the 18MP resolution, I can 't help but shake my head in disagreement. The field of view is drastically different, and as a result, the bokeh isn't anywhere near as appealing. It's almost akin to comparing APS-C and APS formats.
Nevertheless, outside of these issues, the Canon EOS 7D is a remarkable camera boasting an extensive range of features and a powerful autofocus system with numerous functions. Operating the camera is an incredibly enjoyable experience, as long as these previously mentioned limitations don't come into play.