The Canon EOS Rebel XSi (EOS 450D) is Canon's latest DSLR and the most full featured entry level DSLR in their Digital Rebel line of cameras. It builds on the Digital Rebel XTi but adds a new sensor (12MP vs. 10MP), a larger LCD screen (3" vs. 2.5"), Live View, Spot Metering, ISO display in the viewfinder, Highlight Tone priority, High ISO noise reduction and a number of other software features, which are also found on the Canon EOS 40D.

 

Externally, the Rebel XSi and XTi are very similar in size and shape and share a similar control layout. Due to the larger LCD screen of the XSi, a number of the control buttons have been relocated, but the same functionality is retained. To allow the center button of the rear 4-way controller to now activate the Live View mode, a separate ISO button has been added next to the main control dial.

For the first time on any EOS DSLR, the Digital Rebel XSi uses only an SD(HC) memory card for image storage. All previous Digital Rebels, as well as the EOS 5D/10D/20D/30D/40D have used Compact Flash memory cards. The 1D series DSLRs have had the capability of using both SD and CF cards. The change isn't really a big deal since SD cards (and higher capacity SDHC cards) are now as easily available as CF cards, cost around the same in $/GB, and can be found in capacities of up to 16 and 32GB.

Both the XTi and XSi use a pentamirror viewfinder system, but the viewfinder screen of the XSi is slightly larger and also, to my eye, appears to be slightly brighter. The difference in size isn't huge, but every little bit helps. The viewfinder screen of the XSi has a center circle which makes the area of the spot meter. Both cameras use the same diamond shape of 9 focus zones.

The Canon Digital Rebel XSi can be purchased from amazon.com in the following combinations:

• Canon Digital Rebel XSi, $744
• Canon Digital Rebel XSi (black), 18-55mm kit, $834
• Canon Digital Rebel XSi (silver), 18-55mm kit, $900

If you are new to digital photography, start with the photo.net article on "Building a Digital SLR System."

Operating Speed

The Digital Rebel XSi is very responsive in terms of operational speed. The LCD display appears less than a second after the camera is powered up, but you can take a photo only 250ms (1/4s) after the power switch is moved to "on" before the LCD screen starts displaying data.

In continuous capture mode, the Rebel XSi is capable of 3.5 frames per sec (fps) for about 55 frames before the buffer fills and the rate drops a little. The buffer is significantly smaller when capturing RAW, and in that case the 3.5 fps drops to around 0.7 fps after only 6 frames. In RAW+JPEG mode, the buffer only holds 4 captures.

These numbers make the XSi faster than the XTi (3 fps) with a larger JPEG buffer (55 frames vs. 30 frames). However, the RAW file buffer is somewhat smaller (6 frames vs. 10 frames), presumably at least in part due to the larger file size dictated by the higher pixel count. The EOS 40D is good for 6.5 fps for around 125 JPEGs or around 18 RAW images.

Controls

The Rebel XSi uses a control layout, which should be fairly familiar to most users. The 3" rear LCD screen is used to display operating parameters and the various software menus, as well as to review images. As with previous Digital Rebels, there is no top mounted LCD screen. Menu navigation is done via the 4-way buttons (allowing navigation up, down, left and right through the menus). The center "set" button is also used to enable Live View modes. In Live View, focusing is enabled by pressing the "*" button. When not being used for navigation, the 4-way buttons are used to select capturing mode, metering mode, AF mode, and picture style.

 

 

The menu structure is similar to that of the Digital Rebel XTi and the EOS 40D. Like the 40D there's a customizable menu screen on which you can place the functions you use most so that you can access them rapidly. I put Image Quality Selection, Memory Card Format, High ISO Noise Reduction, Highlight Tone Priority, Mirror Lockup, and Custom WB there.

For a complete and detailed description of all the camera controls and options, you can download a PDF copy of the Rebel XSi user manual.

Auto Focus

The EOS Rebel XSi has a 9-point wide area AF sensor with the points set in a diamond pattern. The focus point can be manually selected, or the camera can decide which AF point(s) to use. There are 4 focus modes: One-Shot AF, AI Focus AF, AI Servo AF, and Manual. The central AF point is an improved cross type sensor with high precision for lenses with an aperture of f/2.8 or faster.

In Live view there are two focus modes. One is the same as that used on the EOS 40D, where the reflex mirror flips down briefly and the normal AF sensors are used to achieve focus. This is termed "quick mode." The second focus mode (only available on the XSi) is "live mode" and uses a contrast-based AF system. The live image is used and focus is determined by looking for maximum contrast. It has the advantage that the LiveView is not interrupted, but it's significantly slower (focus may take a few seconds) and it may not be quite as accurate in all situations as quick mode.

Overall, I found that most of the time the AF performance of the XSi and XTi were quite similar. However, there were some situations in very low light where the XSi could get an autofocus lock, while with the same lens under the same lighting, the XTi failed. This is consistent with a statement found in the press release for the XSi in which Canon states, "The EOS Rebel XSi Digital SLR utilizes a precise nine-point Autofocus (AF) system featuring a newly developed AF sensor that improves the camera's subject detection capabilities compared to earlier models."

Metering and Exposure

The XSi adds Spot metering to the Evaluative, Partial and Centerweighted patterns of the XTi. The spot metering area is marked by a circle on the viewfinder screen.

Digital Rebel XSi metering:

• 35-zone TTL full-aperture metering
• Evaluative metering (linkable to any AF point)
• Partial metering (approx. 9% of viewfinder at center)
• Spot metering (approx. 4% of viewfinder at center)
• Center-weighted average metering
• Range EV 1-20 (at 73°F/23°C with EF 50mm f/1.4 USM lens, ISO 100)

The Rebel XSi has the same Highlight Tone Priority feature as the EOS 40D. This appears to be a hardware function, which adjusts the tone curve in order to prevent blowing out highlights in a scene that would normally exceed the dynamic range of the sensor. Exactly how Canon does this, they don't say, but it is more than just a software function. It affects both RAW and JPEG files. It's not a miracle cure for blown highlights, but it does give you about an extra stop of latitude at the expense of potentially more shadow noise. With Highlight Tone Priority enabled, the ISO range is restricted to 200-1600.

The XSi uses a 14-bit A/D converter, which could in theory give better tonal gradation, though in practice it's very difficult to see the difference from 12-bit images (such as those from the XTi).

White Balance

The XSi has the usual set of white balance modes: Auto, Daylight, Shade, Cloudy, Tungsten, White Fluorescent Light, Flash and Custom. It doesn't allow color temperature to be set as the EOS 40D does. In typical Canon fashion, Auto white balance doesn't do great under tungsten lighting, giving a distinctly yellow image. In tungsten mode the color balance under domestic tungsten lighting is closer to neutral, but still noticeably warm. If you want the most neutral color rendition under tungsten lighting, the custom WB mode is best. In this mode you first shoot an image of a white or gray card under the lighting conditions you will be using. The camera can them use this as a reference for subsequent shots.

LCD Monitor

The XSi has a 3" (diagonal) LCD screen vs. the 2.5" screen of the XTi. Both have 230,000 pixels, 100% image coverage and LCD brightness control with 7 levels. The XSi adds the option of 4 different color schemes for data display - black on white, white on black, light blue on dark blue and dark brown on light brown.

 

 

Viewfinder

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The viewfinder of the Digital Rebel XSi is slightly larger than that of the XTi, but slightly smaller than that of the EOS 40D. The differences are not huge and you might not even notice them unless you compared the cameras side by side. The XSi viewfinder also seems slightly brighter than that of the XTi, but again the difference is small. Both the Xsi and XTi use a pentamirror system rather than the more expensive and heavier (but slightly brighter) pentaprism system.

Like the EOS 40D, the Rebel XSi displays the ISO setting in the viewfinder at all times, along with the usual information such as shutter speed, aperture, exposure compensation, flash status, AF status, buffer frames remaining (when that number is 9 or less), flash exposure compensation setting, high speed sync setting and exposure lock indication.

The XTi and XSi share the same 9 AF zone markings, but the XSi viewfinder adds a center circle marking, which defines the area covered by the new spotmeter in the XSi.

XSi Viewfinder Specifications

• Coverage - Vertical/Horizontal approx. 95%
• Magnification - Approx. 0.87x (-1m with 50mm lens at infinity)
• Eyepoint - Approx. 19mm (from eyepiece lens center)
• Dioptric Adjustment Correction -3.0 to +1.0 diopter

Digital Sensor

The Digital Rebel XSi uses a new sensor with 12.2 MP and a maximum image size of 4272 x 2848 pixels. This is up by about 20% from the 10.1 MP sensors used in the Digital Rebel XTi and EOS 40D (3888 x 2592 pixels) and should theoretically enable about 10% greater linear resolution.

In practice, there's not a very noticeable difference in image resolution as you can see from the sample images below. These are 100% crops from JPEGs taken using the standard default parameters for sharpness with each camera.

 

 

The Rebel XSi may have a slight resolution edge, but remember these crops represent looking at sections of a very large image, probably something around 24" x 36" on a typical monitor screen. Despite the fact that both the EOS 40D and Digital Rebel XTi have the same pixel count, the EOS 40D image looks a little sharper. In all three cases, resolution may be increased slightly when capturing in RAW mode and making the optimal conversion to JPEGs.

The Digital Rebel XSi has "anti-dust" features built into the sensor, which includes an anti-static coating and an ultrasonic shaker to dislodge dust particles. There's also a software mapping function, which can be used to minimize the visibility of dust particles if for some reason you can't clean the sensor or you want to be absolutely sure of minimizing the effects of dust.

ISO Settings and Image Noise

Both the Rebel XSi and XTi have an ISO range of 100 to 1600 in full stop steps (100, 200, 400, 800, 1600). The EOS 40D has a range of from 100 to 3200, with the 100-1600 range covered in 1/3 stop steps (100, 120, 160, 200 etc.). An Auto ISO mode is available on the XSi and EOS 40D, but it's limited in its range. In most exposure modes the range is 100-800, but in manual exposure mode ISO is set to 400 in auto mode. In the basic zone modes (everything except P, Av, Tv, M and A-Dep), ISO is always set to auto mode and cannot be manually selected.

In the set of test images below the three cameras are compared. Again all three cameras were set to their default settings and no additional noise reduction functions were enabled. These are 100% crops, meaning one pixel on the screen maps directly to one pixel in the image. Up to ISO 400 all three cameras give very clean images with little or no evidence of noise. At ISO 800 noise starts to appear, but is still well controlled. At ISO 1600 noise is much more visible, with the EOS 40D showing the least noise, followed by the 12MP Rebel XSi and with the 10MP Rebel XTi showing slightly more noise.

 

 

Since a higher pixel count in the same sized sensor usually means smaller pixels, and since smaller pixels usually show higher noise levels at high ISO settings, these observations are consistent with what you would expect. However, noise is still pretty well controlled, even at ISO 1600 on the XSi and it's low enough that small to medium sized prints made from the images would be quite acceptable.

A feature of the EOS 40D, which has found its way onto the XSi is a high ISO noise reduction mode. This appears to increase the amount of chroma noise reduction while not greatly affecting the luminance noise. The main downside of enabling high ISO noise reduction is that the camera can buffer fewer images when capturing in continuous mode. Presumably this is due to the increased processing power required for the noise reduction mode leading to slower compression and storage of images, so the buffer fills faster.

Live View

For the first time in a Digital Rebel series DSLR, Canon has added Live View to the XSi. Live view gives you a real time image on the LCD screen, just like a P&S digicam. To do this the reflex mirror is locked up, and in that position the camera can't use its normal AF sensors.

The XSi has two different methods of autofocusing while using the LiveView mode. The first is the same as that used on the EOS 40D. Pressing the "*" button on the back of the camera drops the mirror down and enables normal AF operation - though the image on the LCD blanks out during this process. When the "*" button is released, the mirror flips back up and the LCD displays the image in real time again. Although this sounds complex, it happens quite fast and Canon call this the "Quick" AF mode.

The XSi also offers another focus mode (not found on any other Canon DSLR at the moment), which they call the "Live" mode. In this mode the image is continuously displayed on the LCD and the camera uses that image to find focus via a contrast sensing algorithm. The drawback of this mode is that it can be slow (focus may take several seconds) and it may not be as sensitive or accurate as the normal "Quick" AF mode using the dedicated phase detection AF sensors.

It's also possible to use manual focus of course, and the LCD image can be magnified by 5x or 10x to assist in optimizing focus.

In-Camera Editing

Though you can't actually edit the images in the camera once you have taken them, you can apply effects to existing images when printing directly from the camera. These include a "Vivid" mode which increases saturation for more vivid greens and blues, a noise reduction mode to lower image noise and three black and white modes (neutral, warm and cool).

The Digital Rebel XSi does have an extensive set of options, which you can select before an image is taken and affect the resulting JPEG image. There are preset picture styles (Standard, Portrait, Landscape, Neutral, Faithful and Monochrome) - all of which can be edited and modified for sharpness, saturation, contrast and color, as well as monochrome color filtering simulation (yellow, orange, red and green). You can also create 3 custom picture styles based on modified existing styles and you can create entirely new styles with the provided Picture Styles Editor software.

If you choose to capture in RAW mode, the provided DPP (Digital Photo Pro) software allows you to apply any picture style to any image during the RAW conversion process.

Flash

The XSi has a retractable pop-up flash with a Guide number of 13/43 (ISO 100 meters/ft). At ISO 400 with an f/4 lens, the flash range is around 6.5m (21.5ft). The flash covers the frame seen by a 17mm (or longer) lens mounted on the XSi. Recycle time is approximately 3 seconds.

The XSi has a standard Canon hotshoe and is compatible with all of Canon's EX series speedlites (the current models are the Canon Speedlite 220EX Flash, $125, Canon Speedlite 430EX Flash, $235 and Canon Speedlite 580EX II Flash, $385 (review)). There's no PC connector for external studio flash, though of course hotshoe to PC adapters are available. Max sync voltage is 250v and the max sync speed is 1/200s.

Memory Cards

The Digital Rebel XSi uses SD/SDHC memory cards. This is in contrast to all previous Digital Rebels and the EOS 5D/20D/30D/40D models, which use Compact Flash (CF) cards. These days, there's little difference between SD and CF cards in terms of price, capacity and availability. The fastest CF cards are still faster than the fastest SD cards, but in a Digital Rebel or even an EOS 40D, the camera can't write fast enough to make use of the extra speed of the fastest cards.

The only real issue related to SD/SDHC and CF cards is compatibility with what you already own. Today, most digital P&S cameras use SD cards, so if you carry a P&S digicam and an XSi you'll only need to carry one type of card.

Batteries

The XSi uses Canon Battery Pack LP-E5, which is currently only used by the XSi. The XTi uses a type NB-2LH battery pack. The new LP-E5 has higher capacity, but a different form factor so the two types of battery are not interchangeable.

AC power can be supplied to the XSi via AC Adapter Kit ACK-E5. An optional Battery Grip BG-E5 is available, which can use 6 AA batteries or two LP-E5 batteries. It also provides a shutter button and control dial along with AE/FE Lock, exposure compensation and AF point selection buttons in a vertical orientation.

Mechanical Design

The Digital Rebel XSi is very similar in size and shape to the XTi. The edges and corners are slightly more rounded and the rubberized patches on the back and grip sections of the camera are slightly rougher and "stickier", making the camera a little easier to hold with one hand.

 

• Digital Rebel XSi - 129 x 98 x 62 mm - 524 g (with battery)
• Digital Rebel XTi - 127 x 94 x 65 mm - 556 g (with battery)

Like the XTi, the XSi has a high strength plastic mirror box mounted in a small stainless steel chassis. The outer panels of the XSi are made from durable plastic.

Choosing a Lens

The Digital Rebel XSi is available as a kit with the new Canon EF-S 18-55mm f/3.5-5.6 IS, $170 (review). This lens covers the same angle of view that a 29-88mm zoom would on a full frame camera, so it's useful for many types of photography including landscapes, group shots and portraits. The Image Stabilized (IS) system is a new low-cost version of Canon's traditional IS, but the performance is good and it can add up to three stops of stability, making handholding the lens in low light easier, despite the relatively slow maximum aperture.

 

To complement the EF-S 18-55/3.5-5.6IS Canon has a new Canon EF-S 55-250mm f/4.0-5.6 IS, $299 (review), which is good for situations like sports and wildlife photography where a longer focal length is needed. It gives an angle of view equivalent to an 88-400mm lens on a full frame 35mm camera. Like the EF-S 18-55IS, the EF-S 55-250IS uses a new, lower cost IS system, but again it seems pretty effective adding up to three stops of stability. Zoomed out to 250mm, IS gives you a good chance of a sharp image while handholding the camera at shutter speeds as low as 1/60s.

Of course, for an inexpensive fast portrait lens, you really can't beat the Canon EF 50mm f/1.8 II, $80 (review). That's a lens I always recommend looking at.

There are many other lens options from Canon, Sigma, Tamron and Tokina. For an overview of what's available see The EOS System Guide

Compared to Nikon, Canon, Pentax, Sony

The 12MP Digital Rebel XSi falls between the 10MP Canon Digital Rebel XTi, $545 (review) and the 10MP Canon EOS 40D, $1133 in Canon's lineup. The XTi doesn't offer such features as Live View, spotmetering or Highlight Tone Priority. The EOS 40D offers those, plus a higher frame rate (6.5 fps vs 3.5 fps), a larger image buffer, support for studio flash, and a more rugged construction. Which DSLR to choose depends on your needs and how much you want to pay. All three cameras are capable of producing excellent image quality, so the choice should be mainly based on camera features.

In the Nikon lineup the closest cameras to the Digital Rebel XSi would be the 10MP Nikon D40x, $590 (review)Nikon D40x and the 10MP Nikon D80, $1000 (review) Nikon D80. The D40x is cheaper, but has a simpler 3 zone AF system and no provision for the use of Nikon AF-S (internal ultrasonic motor) lenses. The D80 is closer to the XSi in terms of features, having an 11-zone AF system, DOF preview and an optional vertical grip (all of which the D40x lacks). Both the D40x and D80 have the option of an ISO 3200 setting, which could be a consideration for those who do a lot of low light work.

The 10MP Pentax K200D, $619, is the closest camera to the XSi in the Pentax lineup. It offers several features not found on similar Canon and Nikon DSLRs including sensor-shift stabilization built into the camera body. This means that all your lenses become stabilized and you don't need to buy special IS or VR lenses. The K200D is also sealed against dust and moisture to a greater extent than most other DSLRs of its class. It features an 11-point AF system and an ISO range up to 1600. It does not have a Live View capability.

The Sony Alpha A350, $800 (review) offers a 14MP sensor, ISO 3200 capability, an advanced Live View system, a tiltable 2.7" LCD, sensor-shift stabilization built into the camera body and a 9-zone AF system. Maximum frame rate is a little slow at 2 fps, but it does pack in a lot of features for around the same price as the Rebel XSi.

Rebel XSi Key Features

• 12MP CMOS sensor
• 14-bit A/D conversion
• Digic III processor
• 3" LCD
• Live View with Live Focus
• Highlight Tone Priority
• High ISO noise reduction
• ISO 100-1600 (plus Auto)
• ISO visible in viewfinder
• Flash Sync speed 1/200s
• Spot metering (4%)
• Mirror Lock Up
• Depth of field preview
• Picture Styles

Conclusion

The Rebel XSi seems to be a combination of the Rebel XTi and the EOS 40D, with a few new features of its own thrown into the mix. It has the basic form of the XTi with the same shutter speed range, the same flash sync speed and the same ISO range. However it also has features of the EOS 40D such as Live View, Highlight Tone Priority, High ISO Noise reduction, Spot metering, a 14-bit A/D converter and viewfinder ISO display.

The performance is perhaps closer to the 40D than to the XTi. Resolution is measurably higher, though the difference in practice is quite small. Noise appears to be a little higher, perhaps because of the smaller pixels.

Overall the XSi is an improvement over the XTi, though more in terms of features than image quality, which is good in both cameras. Upgrading from the XTi to the XSi makes sense if you need things like spot metering, a larger LCD and Live View, but if you're looking for a noticeable leap in image quality, I don't think you'll see it. If you want a significant increase in image quality, you'd probably need to look at a full frame DSLR like the Canon EOS 5D, $1890 (review).

Where to Buy

Amazon.com offers the following Digital Rebel XSi combinations:

 

• Canon Digital Rebel XSi, $744
• Canon Digital Rebel XSi (black), 18-55mm kit, $834 (review)
• Canon Digital Rebel XSi (silver), 18-55mm kit, $900 (review)