Although the Digital Rebel XSi resembles the XTi, it is just a touch larger. There have been changes to the control layout, especially on the back of the camera. Weighing in at a mere 16.8 oz./ 475g (body only) the XSi is almost 2 ounces lighter than the XTi and very comfortable to carry. The textured grip offers firm control and the button count has been reduced as Canon strives to make the Rebel simple to use. Looking at the silver model above you can clearly see the textured thumb pad on the back of the camera.

CMOS Imager

The XSi's improved, 12-megapixel, CMOS (complementary metal oxide semiconductor) sensor captures images with excellent tonal range, and offers the most pixels in its class. It offers many of the same new technologies first introduced on the EOS-1D Mark III model. It's an APS-C size sensor (22.2 x 14.8mm), and there's an effective 1.6x increase in the lens's marked focal length. Analog to digital signal conversion is handled by a 14-bit processor, which generates smooth transitions from light to dark colors, with far less risk of any color banding. A Highlight Tone Priority option, made possible by the 14-bit color space, allows you to increase the level of detail in bright areas of a scene up to one stop, without affecting overall exposure.

DIGIC III Image Processor

Developed to maximize performance between the capture and recording stages of digital photography, the EOS Rebel XSi's latest-generation DIGIC III Image Processor works with Canon's CMOS sensor to achieve higher levels of performance. The entire electronic system has been totally redesigned, giving the camera its incredible combination of speed and image quality. Digital noise is significantly reduced in shadow areas, and color reproduction is superior.

EOS Integrated Cleaning System

I don't need to tell you how dust on the image sensor can ruin a great photo. Thankfully the Canon EOS Integrated Cleaning System is there to save the day. The Canon-designed Self Cleaning Sensor Unit uses a low-pass filter at the front of the sensor to shake off dust automatically with ultrasonic vibrations, removing dust from the sensor assembly. The EOS Rebel XSi has a new coating on the front surface of the low-pass filter, to increase its resistance to dust sticking to the sensor.

Dust Delete Data Detection

Dust on the sensor can also be "erased" with the included Digital Photo Professional (DPP) Version 3.3 software. A simple test shot of a plain, white object can be taken, then the Dust Delete Data image is analyzed in-camera, and the location and size of any remaining dust is added to any subsequent pictures taken. This data is transmitted along with the image, whether JPEG or RAW, and can be either manually or automatically erased in Canon's DPP software. This added software option helps you achieve the cleanest possible image.

XSi Lens Mount

The Rebel XSi is compatible with all Canon lenses in the EF and EF-S lineup, ranging from ultra-wide angle to super telephoto lenses. Special optical technologies, such as Aspherical, ultra-low dispersion, or fluorite elements are featured in the L Series lenses, and Canon's Optical Image Stabilizer technology is available in select lenses to minimize the effect of camera shake

We received 2 EFS lenses with our XSi. Shown above is the EF-S 18-55mm f/3.5-5.6 IS - a standard zoom lens made exclusively for the EOS Digital Rebel and EOS 20D SLR cameras with APS-C size image circle - equivalent to an approx. 28-90mm focal length. The lens is compact and ultra-lightweight with an impressive close-focusing ability of 0.9 ft (0.28m) and features an optimized coating to minimize ghost images and flare. This lens can only be mounted on the Digital Rebel, EOS 20D, EOS 30D, Digital Rebel XT, Digital Rebel XTi and the XSi.

I also got to use the EF-S 55-250mm f/4-5.6 IS lens. This telephoto zoom lens is designed with Canon's Optical Image Stabilizer technology yet quite lightweight and is equivalent to a focal length of 88-400mm in the 35mm format. The image stabilizer effect is equivalent to a shutter speed about 4 stops faster than the same size lens without Image Stabilizer. It uses a UD-glass lens element to correct chromatic aberration for excellent image quality.

Autofocus System

A 9-point wide area AF sensor offers fast, accurate focus. It has multiple focus modes available, including One-Shot AF, AI Focus AF, AI Servo AF and Manual. In Live View Function, the EOS Rebel XSi has two AF modes: Quick mode, which uses the camera's standard 9-point AF system, and Live mode, which is a contrast-based AF system that reads the sharpness of subjects right from the imaging sensor, and can be overridden by pressing the AF mode selection button. A familiar feature in PowerShot cameras, Live mode AF uses similar technologies to achieve focus, while Quick mode is more appropriate for capturing action or for shooting in low light.

E-TTL II Flash

The XSi has a built-in, retractable, auto pop-up flash with a Guide Number of 13/43 (ISO 100, in meters/feet). The flash has a recycling time of a approximately 3 seconds and a flash-ready icon that is visible in the viewfinder. Flash exposure compensation is available is ±2 stops in 1/3- or 1/2-stop increments,

A 35-zone metering system analyzes light based on each zone in the viewing area, enabling the camera to choose the overall best exposure for the entire scene. The XSi now features a spot meter, which reads a tiny area (about 4%) of the image for precise metering. It also provides Center-weighted average metering and partial metering for accurate exposure no matter the situation.

The Canon Speedlite 430EX is the ideal accessory for the Rebel XSi. It has a maximum guide number of 141 ft./43m at ISO 100), and is the perfect when you can't get right up to the subject. The 430EX is also great for bounce flash, with its tilting and swiveling flash head. It automatically zooms the flash head to cover lenses ranging from 16mm up to 105mm or longer with the EOS Rebel XSi. Of course, it works with the camera to provide full E-TTL II automatic flash exposure. And the 430EX has a powerful AF-assist beam, which allows the camera to autofocus, even in nearly total darkness, on subjects as far as 32 ft. from the camera.

Improving on the previous model, Speedlite 420EX, the new 430EX can now be set to manual flash mode (full power~1/64). Flash compensation can be set on the flash unit, and manual control of the flash zoom head is now possible. Improvements in its circuitry make recycle time 40% faster and fully compatible with Canon's wireless E-TTL.

Viewfinder

The XSi also has an improved, high magnification viewfinder that provides a larger overall view, and increased brightness and clarity. A Display-Off sensor automatically turns the LCD monitor off whenever the camera is brought to your eye. All relevant shooting information is displayed right in the viewfinder so it's easy to check your settings without moving the camera away from your eye.

The eyelevel viewfinder shows approx. 95% of the captured image with 0.87x magnification (-1m with 50mm lens at infinity). There is a built in -3.0 - +1.0 diopter adjustment. Around the viewfinder is a soft rubber eyecup that fits comfortably against your face or eyeglasses, it provides a 19mm eyepoint.

Visible inside the viewfinder are the focusing points - the active focus point(s) are illuminated to indicate which AF zone(s) are selected. Viewfinder information includes AF information (AF points, focus confirmation light), exposure information (shutter speed, aperture, AE lock, exposure level, ISO speed, exposure warning), flash information (flash ready, high-speed sync, FE lock, flash exposure compensation), monochrome shooting, white balance correction, maximum burst and SD memory card information.