BY: J. Keenan, DigitalCameraReview.com Contributor
With the recent introduction of the 18 megapixel Canon EOS 7D, the EOS DSLR family boasts a fairly linear progression of resolutions in a product lineup that formerly had a gap between the 15.1 and 16.1 megapixel offerings and the 21.1 megapixel models. Now Canon DSLRs can be had with 10.1, 12.2, 15.1, 16.1, 18 and 21.1 megapixel sensors. Nobody else comes close to offering such a range. And while the 7D bears some family resemblance to the 50D in terms of size and the 5D Mark II in weight, don't get the idea it's just another model with different resolution. New is the operative word for the 7D - as in a number of new features never before seen on any Canon EOS DSLR.
There's a new 19 point autofocus system with all cross-points; a new iFCL (intelligent focus, color and luminance) metering system with 63 zones; a new intelligent viewfinder and a continuous shooting rate of up to 8 frames per second (fps). There's a new electronic level and the new sensor retains the Canon APS-C sizing of 22.3x14.9mm, resulting in a 1.6X crop factor. Dual Digic 4 image processors help handle the large files and continuous shooting rate. The camera is the third EOS to shoot full HD (1080p) video and accepts type I and II CF cards and UDMA-compliant CF card media.
Available as a body-only, the camera will also be offered in a kit with Canon's EF 28-135mm f/3.5-5.6 IS USM zoom lens per a Canon U.S.A. press release. Canon includes an eyecup, neck strap, stereo AV and USB interface cables, a battery pack and charger, CD-ROM software and printed instruction manual with each camera.
That same press release calls the 7D "... the most functional and innovative DSLR Canon has released to-date." Sounds good on paper - let's see how it does in the field.
BUILD AND DESIGN
The 7D features a magnesium alloy body with dust and moisture resistance, as well as a shutter tested to 150,000 actuations. Build quality of even entry level DSLRs has always been good in the units from various manufacturers I've tested, and the 7D looks to be well constructed and robust. The materials, particularly the rubber-like patches applied to gripping surfaces seem to be a cut above the entry level units, as befits a body carrying a $1700 price tag.
While the camera will be largely familiar to Canon DSLR users, there are some differences in control placement from other current models in the Canon lineup. I suspect folks moving into a 7D from another Canon body will be coming mostly from the 50D/40D/entry level user's group, rather than the 5D/5DII or 1D crowd, so we'll discuss the differences relative to the 50D in the next section.
Ergonomics and Controls
The 7D has a deeply sculpted handgrip and prominent thumb rest on the right front and rear of the camera body, respectively. There is ample room for finger clearance from the lens mount/lens barrel in the front, and the shooting finger falls naturally across the shutter button. The thumb rest at the rear supports the thumb nicely as well. While I don't shoot Canon DSLRs, I have held and played with most of the current lineup in camera stores - not the most intensive study to be sure - and I like the feel of the 7D in my hand the best. This a purely subjective judgment and might well be influenced by having the 7D to use for about a month, but the other Canon bodies just didn't feel quite as good.
Camera back control layout differs from the 50D in both number of controls and location in some cases. The AF-ON, AE Lock and AF point selection/magnify buttons occupy similar locations on both cameras, as do the quick control dial and multi-controller. The 7D adds a live view shooting/movie shooting switch and start/stop button above the multi controller, and moves the erase, playback, info, and picture style selection buttons from the horizontal configuration below the monitor to a vertical alignment below the menu button to the left of the monitor.
The electronic level (pitch and roll) can be displayed on the LCD monitor or in the viewfinder. Here's the level on the monitor - you can display it with the camera set for normal shooting (Level photo) and also with the camera set to shoot in Live View (Level 2 photo) - in the viewfinder focus points illuminated in red indicate the camera attitude.
The 7D also adds a quick control button (the first EOS to do so) above the menu button and morphs the live view shooting/print share button into a RAW-JPEG/direct print button. Pushing this button brings up a screen allowing access to a number of camera shooting settings without having to resort to internal menus.
Quick menu
The RAW/JPEG button provides a quick transition to the simultaneous RAW/ JPEG shooting mode from whatever image quality setting was previously selected: it will capture a RAW file in addition to a JPEG setting or a large JPEG file in addition to a RAW setting.
The function button of the 50D is gone from the 7D, and the power switch moves from adjacent to the quick control dial to beneath the mode dial on the top left of the body - making turning the camera on a two-handed proposition. The former power switch of the 50D becomes a quick control dial lock on the 7D.
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The 7D also adds a multi-function button near the main dial on upper right of the camera body; the rest of the control buttons atop the body remain largely unchanged as to location.
Menus and Modes
Canon must be trying to cast a wide net in attracting potential customers to the 7D - in addition to the usual DSLR manual and semi-automatic shooting modes, the 7D tosses in a couple of fully automatic modes that offer few user inputs - the kind of modes typically found on point and shoots and entry level DSLRs.
- Full Auto: the camera handles pretty much everything, the user can select image quality and single shots or self-timer.
- Creative Auto: the camera handles pretty much everything, but the user has expanded input options including image quality, single or continuous low speed shooting, self timer, some color options, exposure compensation and blurred or sharper background.
- Program Auto: camera sets aperture and shutter speed and user has wide variety of inputs.
- Aperture Priority: user sets aperture, camera sets shutter and user has wide variety of inputs.
- Shutter Priority: user sets shutter speed, camera sets aperture and user has wide variety of inputs.
- Manual: user sets aperture and shutter speed, has wide variety of inputs.
- Bulb: shutter stays open while shutter button is held down, user has wide variety of inputs.
- Camera User Settings: three custom modes that allow the user to register preferred camera settings and functions for quick recall.
- Movie: can capture 1920x1080p at 30, 25 or 24 fps; 1280x720p at 60 or 50 fps and 640x480p at 60 or 50 fps.
Display/Viewfinder
The 3.0 inch LCD monitor is of approximately 920,000 dot composition and adjustable for seven levels of brightness. The monitor is usable for image composition and capture in all but the harshest conditions of bright outdoor light, though there are times when it becomes inadequate for the task; coverage is 100%.
The eye-level pentaprism viewfinder features a diopter adjustment to accommodate varying degrees of eyesight and offers 100% coverage.
PERFORMANCE
Aside from smoothing the pixel gap in the Canon sensor lineup, the 7D gives Canon a good performing camera at a price range that just happens to also fit into a gulf between the $1100 MSRP of the 50D and the $2700 ticket to ride with a 5DII. Price or pixels - take your pick and
Canon has you covered either way.
Shooting Performance
The 7D, like any higher performance DSLR, starts and shoots virtually instantly. Sensor cleaning when the 7D power switch is set to ON or OFF is the default, and on startup takes a little over 3 seconds. You can abort the sensor cleaning by going to a half push on the shutter button to begin shooting immediately, or the cleaning can be disabled via internal menu.
Shutter lag is basically non-existent and AF acquisition time is excellent as well, with the figures coming in at 0.02 and 0.17 seconds, respectively. Single shot-to shot times (shoot, write, reacquire focus and shoot) are practically as fast as you can get off the first shot, lift off the shutter and take the next shot - something in the order of 0.8 seconds.
Shutter Lag (press-to-capture, pre-focused)
| Camera | Time (seconds) |
| Canon EOS 7D | 0.02 |
| Nikon D300S | 0.02 |
| Pentax K20 | 0.04 |
| Panasonic Lumix DMC-GH1 | 0.06 |
AF Acquisition (press-to-capture, no pre-focus)
| Camera | Time (seconds) |
| Nikon D300S | 0.15 |
| Canon EOS 7D | 0.17 |
| Pentax K20 | 0.28 |
| Panasonic Lumix DMC-GH1 | 0.37 |
Continuous Shooting
| Camera | Frames | Framerate |
| Canon EOS 7D | 160 | 8.0 fps |
| Nikon D300S | 14 | 6.9 fps |
| Pentax K20 | 38 | 3.0 fps |
| Panasonic Lumix DMC-GH1 | 5 | 2.8 fps |
*Note: Continuous shooting framerates are based on the camera's fastest full-resolution JPEG continuous shooting mode, using the fastest media type available (300x CF, SDHC, etc.). "Frames" notes the number of captures recorded per burst before the camera stops/slows to clear the buffer.
Continuous shooting speed can be as fast as 8fps - faster than anything from Sony, Pentax, Olympus and Fuji; matched by the Nikon D300/300S with the optional MB-D10 battery pack and surpassed only by the Nikon D3 and Canon EOS 1D/III and IV. Using Lexar UDMA 300X CF cards I got between 16 and 20 continuous RAW files at the 8fps rate before the 7D needed a short break.
Using a 600X SanDisk Extreme Pro UDMA 6 card, the camera also captured 16 to 20 files before stopping, but write times with the 600X card were significantly better - about 6.5 seconds to clear the buffer versus 11 seconds with the 300X.
Our studio tests got 160 JPEGS, only about 140 more than the longest sequence I've ever shot in the field. Here are four shots from a sequence at 8fps - the advantage of the higher speeds is you get the "in between" shots the 4 and 5 fps cameras miss. If you compare the first and third shots and particularly the second and fourth, you can get an idea of how much can be missed shooting at the lower rates.
 Burst Shooting Frame 1 |  Burst Shooting Frame 2 |
 Burst Shooting Frame 3 |  Burst Shooting Frame 4 |
The EOS 7D carries a new Canon AF system consisting of 19 cross-point sensors (cross-point sensors can establish focus in both horizontal and vertical planes). There are 5 AF area selection modes: single point (manually selected); zone AF (the 19 points can divided into 5 separate zones covering various portions of the field of view); auto select 19 point AF (used in the fully auto and creative auto shooting modes); spot AF (same as point AF but the AF point covers a smaller area than in point AF) and AF point expansion (manual selection of the active point and adjacent points are then also used to aid with focus).
Any of the modes worked well with static subjects, although users should keep in mind when using the auto select or zone methods that all AF points in the selected zone are used to acquire focus and will tend to focus on the nearest subject. For moving subjects I found that AF point expansion worked best - but only after some trial and error. In addition to simply selecting the AF point expansion mode, I ultimately ended up adjusting the AI Servo tracking sensitivity to slow in order to get the best results.
The higher performance DSLRs have a myriad of settings in various menus that impact their performance, and fine tuning these combinations is the key to realizing the full potential of any camera. I shot over 2500 captures in preparing this review, many of them sequences testing the ability of the 7D to acquire and/or keep focus on moving subjects.
Here are six shots from a sequence of thirteen tracking a single gull through some crowded airspace - the 7D did a pretty good job of not losing track of the bird despite a lot of movement in and out of the frame. These were made with the 200mm lens at f/4 to pick up some shutter speed and within thirty feet of the birds so depth of field was fairly shallow. Overall the 7D handles moving subjects well with the right settings in the camera - it's not perfect and will lose track every so often, but it turned in a decent performance.
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The 7D built-in flash has a guide number of 39 at ISO 100, which translates into a range of about 10 feet with the lens set at f/4. Recycle times in moderately lit conditions with a fully charged battery ran only a second or so - and Canon lists three seconds as the nominal recycle rate. When shooting in aperture priority, the flash can be set to fire and illuminate a subject in the foreground while the camera holds the shutter open an extended period to use natural light to expose the background. In this example, the owl in the foreground is lit by the flash while the castle is exposed for the ambient light.
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The 7D flash can also act as the master unit with Canon Speedlite flashes with wireless slave capability and remotely trigger these other flashes to fire.
Canon rates the 7D battery for about 800 shots with no live view shooting and 50% flash usage; that figure drops to about 220 shots using live view and 50% flash. Continuous live view shooting lasts about 90 minutes.
Lens Performance
Canon provided an EF-S 17-85mm f4-5.6 IS USM zoom lens for this review, and also an EF 200mm f2 L IS USM to help us better explore the 7D's potential for sports and action shots with that 8 fps motor. Here's what the wide and telephoto ends of the zoom look like, as well as the 200mm.
17mm wide angle
85mm telephoto
200mm telephoto
Because the 17-85 is not being offered as a kit lens with the 7D I'll just briefly comment that it proved to be a nice walking around lens, not overly fast and exhibiting some barrel and pincushion distortion with straight lines in images. One advantage of the DSLR is that there are usually a large number of lenses available to mate with the body depending on your particular shooting need(s). The 7D accepts both EF and EF-S lenses, which total over sixty at last count.
Video Quality
Video quality out of the 7D at the 1920x1080p HD resolution is good - our demo videos were shot at the "cinema" speed of 24fps, but 30 and 25fps speeds are available as well. The 7D uses a CMOS sensor for video and still image capture, and that type sensor can be subject to "rolling shutter effect" which causes vertical stationary objects to appear to be bending as the camera pans across the scene. The 7D does exhibit this effect, which is slight at normal panning speeds but can be greatly exaggerated by panning quickly back and forth at, frankly, speeds that no reasonable person would ordinarily employ. Panning to follow a fast jet at an air show would be one example where the effect might be more objectionable without purposely trying to initiate the phenomenon.
Reduced resolutions of 1280x720p and 640x480p are also available at 50 and 60 fps rates. Regardless of resolution, video length is limited to 4GB or 29 minutes 59 seconds. AF is available at the start of recording, but continuous AF is not provided. Manual focus and zoom are available, and the 7D also allows for manual exposure in addition to automatic.
Video recording is a simple matter of setting the live view shooting/movie shooting switch to the red "movie" icon, acquiring focus automatically by means of a half push of the shutter or full push of the AF ON button (or focus manually) and pushing the start/stop button to initiate capture. A second push stops recording. As heavy as the 7D is with even the lightest of lenses, a tripod or some other form of camera support is a good idea for extended video shoots. Holding the 7D and lens with even partially extended arms in order to see the monitor will get tiring pretty quickly.
Image Quality
Shortly after the 7D reached market Canon issued a firmware update to correct a problem with ghost-like images in some 7D captures: "In images captured by continuous shooting, and under certain conditions, barely noticeable traces of the immediately preceding frame may be visible. This phenomenon is not noticeable in an image with optimal exposure. The phenomenon may become more noticeable if a retouching process such as level compensation is applied to emphasize the image."
Our demo model 7D displayed no traces of the problem for over 2000 shots, but checking a sequence from an overcast day at the beach I found one example of the phenomenon: two shots of a gull with the ghostly outline of the preceding shot appearing on the second. While I use a calibrated 24 inch LCD monitor to review shots and made the discovery on that screen, the ghost was faintly visible on a 5x7 print I made of the image.
Here are the two shots as they came out of the camera:
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In any event, the firmware update has reportedly fixed the problem, which was subtle, at least on our problem image. Folks contemplating moving into a 7D should plan to update the firmware if their camera hasn't had the latest version installed at the factory.
Default images out of the 7D were generally pleasing with regard to color fidelity, contrast and sharpness, but are output at 72 dpi which results in a 72x48 inch image at 100% enlargement - you're going to be resizing for both printing or internet/email usage.
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Not sure what Canon's thinking is on this one - if the images are output at 300 dpi that resolution is excellent for printing as is, and you're left with resizing for internet/email only.
And while we're on the subject of image size, let's talk about those 18 megapixel resolution files. Conventional wisdom holds that the higher resolutions tend to be attractive to folks who do landscape or scenic shots where the higher pixel counts bring out greater detail in those wide vistas. Studio work is also mentioned - the ability to bring out detail in portraits, or commercial products for example. And finally, more resolution means larger files which can then be cropped more aggressively yet still retain good photo quality, or, in the absence of cropping produce larger images.
Cropping is a useful tool to improve images as long as the perspective of the shot isn't ruined - composing the shot as it will finally appear in the camera is always preferable to a composition that will need surgery in the computer later. Here's the original and a cropped version of an Anna's hummingbird - both at 15x10 inch size with the original at 345 dpi and the crop at 247 dpi.
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With many competitors' cameras carrying 12 megapixel class sensors, the 18 megapixel sensor of the 7D enjoys an almost 50% advantage in pixels. The 7D has sensor pixel dimension of 5184x3456 to produce that 18 megapixels; a Nikon D300s has pixel dimensions of 4288x2848 to produce 12.3 MP.
If we resize both files to 300 dpi for printing, we get a 17.28x11.52 inch print out of the 7D and a 14.29x9.49 inch print out of the D300s. So 50% more pixels doesn't get you a 50% larger print. There's more to work with, but perhaps not the sweeping amount many folks might expect out of such a seemingly large boost in resolution.
The 7D offers evaluative, partial (9.3% at the center of the screen), spot (2.3% at the center of the screen) and center-weighted metering options, with evaluative being the default. In practice, evaluative worked well for a variety of conditions and was used for the captures in this review. The 7D fairly consistently lost highlights in the high contrast surf shots I try to use to test metering systems. However, the highlights were barely being lost and 1/3EV under exposure compensation fixed virtually all the problems.
The 7D offers a highlight tone priority setting that seeks to expand the camera's dynamic range between the standard 18% gray and bright highlights, smoothing out the gradation between grays and highlights. Highlight tone priority helped with the highlights as evidenced by histograms of individual shots, but with the downside that ISO settings from 200 to 6400 are required - the 100 to 200 ISO range is disabled when this setting is enabled.
Canon's picture style effects offer image effects that can be selected to complement a shooting style or subject. Here are the standard, portrait, landscape, neutral, faithful, and monochrome effects. Individual characteristics of each effect (sharpness, contrast, saturation and color tone) can be further adjusted by the user.
 Standard |  Portrait |
 Landscape |  Neutral |
 Faithful |  Monochrome |
Auto white balance worked well for most lighting conditions and shot warm under incandescent light. The 7D also offers daylight, shade, cloudy, tungsten, white fluorescent, flash, custom and color temperature settings.
Auto White Balance, 3200k incandescent light
Generally, adding pixels to the same physical sized sensor increases noise in digital captures - both the additional pixels and their smaller size are largely to blame. But it's also true that technology inexorably marches on and that may be why the 7D noise performance came as a pleasant surprise. The camera doesn't re-write the book on low ISO noise performance, but by the same token noise performance didn't take the hit I thought it would, at least to my eyes.
 ISO 100 |  ISO 100, 100% crop |
 ISO 200 |  ISO 200, 100% crop |
 ISO 400 |  ISO 400, 100% crop |
 ISO 800 |  ISO 800, 100% crop |
 ISO 1600 |  ISO 1600, 100% crop |
 ISO 3200 |  ISO 3200, 100% crop |
 ISO 4000 |  ISO 4000, 100% crop |
 ISO 5000 |  ISO 5000, 100% crop |
 ISO 6400 |  ISO 6400, 100% crop |
ISO 100 and 200 are quite clean and hard to tell apart - 400 is quite good but showing just a hint of noise and 800 a bit more. ISO 1600 is still fairly good but showing more noise, and 3200 has dropped off even more. The biggest individual drop looks to be between 3200 and 6400, both of which I'd try to avoid if possible. The 7D has "standard" high ISO noise reduction enabled as a default and the camera actually applies noise reduction at all ISO speeds - in the low ISO range the effect is primarily reduction of noise in shadow areas. There are also "low" and "strong" reduction settings, as well as a disable option.
Additional Sample Images
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 |  CONCLUSIONS With the introduction of the 7D, Canon has fit a camera neatly into both the resolution and cost gaps that had formerly existed in their DSLR lineup. Now there's a smooth progression of resolution from 10 megapixels to 21 at roughly 2 or 3 megapixel increments, and a $1700 camera to fill the gap between the $1100 50D and $2700 5DII. The Canon EOS 7D is an interesting mix of features - on the one hand it brings a new level of performance to the Canon line with a new AF system, new viewfinder, new metering system, new sensor with dual Digic 4 processors and an 8 fps motor that screams "professional" (or at least loudly proclaims "advanced amateur"). In the next breath we find things like 2 auto shooting modes that could have been pulled right from your daughter's Point and Shoot and a face detection live view shooting mode. Huh? Fortunately, the serious side wins out in the end and Canonistas have a nifty new body to move up to if they're shooting at the entry level now, or a legitimate budget backup to their pro body at the other end of the scale. It's hard to call a $1700 body-only camera "budget", but considering the overall performance of the 7D it's pretty close to being a steal. The autofocus is pretty good, image quality is very good, and ISO noise is good considering the resolution. The camera zings along at 8 fps when it needs to and will do that all day before the buffer fills if you're shooting JPEGS. There's true 1080p HD video if you're into that sort of thing and the whole package is well built and designed to resist the elements.
Cons:
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