Canon EOS 300D Digital RebelCanon knocks the bottom out of the Digital SLR market, with an amazingly affordable, full-featured model!<<Viewfinder :(Previous) | (Next): Exposure & Flash>> Page 5:OpticsReview First Posted: 09/04/2003 |
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The EOS 300D accepts all standard EF-series Canon lenses, a collection that includes roughly 56 currently produced models, and more than 100 released since the series began in 1987. What's news with the 300D though, is the release of a new Canon lens designed for use only with the 300D, the EF-S 18-55mm f/3.5-5.6 lens. Designed with a shorter back focus than what's found on standard Canon EF lenses, the EF-S lens extends further into the camera body and projects an image circle closely matching the size of the sensor itself. (Lenses designed for conventional 35mm film cameras must cover a much larger area.) This new design greatly cuts down on the size and weight of the lens, as well as the production cost, according to Canon. The lens is not available separately, but only as part of the Digital Rebel Kit (which also includes basic accessories). The camera's lens mount now features two alignment symbols: the standard red dot for traditional EF lenses, and a small white square for the EF-S lens.
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Surprising Lens Quality!
The EF-S lens was probably one of the biggest surprises I found in testing the Digital Rebel. - It provides surprisingly high optical quality, particularly impressive for such a low-cost lens. (While it isn't available separately, the mere $100 price differential between the cost of the 300D body alone vs. the cost of the kit including the EF-S lens sets a limit on its likely manufacturing cost.) Apparently, besides reducing the size and cost of the lens elements themselves, the reduction in back focus distance makes it easier for the lens designers to reduce distortion, coma, and chromatic aberration as well. When used on the Digital Rebel body, the 18-55mm EF-S lens delivers image quality as good as that of many of Canon's conventional 35mm-oriented lenses costing many times as much. Looking into the future, I see Canon eventually extending the Rebel camera line with multiple models at a range of price points, and also developing more EF-S lenses, covering a wider range of focal lengths. (In fact, I wouldn't be at all surprised to see the dual EF/EF-S lens mount used on the 300D appearing on higher-end Pro cameras from Canon. - The benefits in terms of optical quality and physical size and weight would appeal to pros every bit as much as to amateurs.)
Canon's EF lens series is known for advanced lens models incorporating Canon's exceptionally fast, silent "ultrasonic" focusing mechanism (a coreless motor built into the lens body itself), and an exceptional range of optically stabilized models that permit hand-holding way beyond light levels that would normally require the use of a tripod. While none of this applies to the EF-S lens, it's good to know that the Digital Rebel can take advantage of lenses having those capabilities. (Interestingly, it appears that while EF-S lenses sold in the US will not have ultrasonic focusing mechanisms, those sold in Japan will. - Canon claims that the difference in focusing speed between the two lens types on the Digital Rebel will be slight, but I'm sure US users would at least like the option to purchase a Rebel with the higher-tech lens. I suspect that the reason for the difference has to do with the lower selling price of the body/lens kit in the US, the magical $999 price point being critical in the US market. - I can also understand that it might not be feasible to introduce two different product SKUs, one with conventional focusing, one with ultrasonic, as retailers would likely "rebel" themselves at that prospect. One can still hope though...)
Like most digital SLRs, the sensor in the EOS 300D is smaller than a 35mm film frame. This means that the "effective" focal length of standard EF lenses will be 1.6x their normal values on 35mm cameras. Just to be clear, nothing's changed about the lenses or their behavior, it's just that the CMOS sensor is effectively cropping a smaller area out of the lens' coverage circle. The net result is that shooting really wide angle photography is tough with digital SLRs, the 300D included. At the other end of the scale though, it's like having a 1.6x teleconverter on your lenses with no cost in light loss or sharpness. Thus, a 300mm telephoto has the same "reach" as a 480mm on your 35mm film camera. And of course, a f/2.8 300mm is a lot cheaper than a f/2.8 500mm! The net of it is that a 31mm focal length has the same angular coverage as a 50mm lens on a 35mm SLR, and the common 16-35mm zoom lenses have a range equivalent to 25.6-56mm on film cameras. Taking the new EF-S lens as a case in point, its 18-55mm focal length translates into an equivalent of ~29-88 mm. (A slightly wider than average wide-angle to a modest telephoto.)
Autofocus System
Like the 10D, the 300D has an autofocus system with seven sensors, arrayed in a cross pattern in the center of the frame. You can manually select which of these you want the camera to pay attention to (handy for off-center subjects), or you can let the camera decide. When it's operating in automatic AF mode, it will use the sensor corresponding to the part of the subject closest to the camera. The EOS 300D's AF system operates in One Shot, AI Focus, or AI Servo AF modes, but unlike the 10D, the 300D doesn't let you decide which AF mode to use. (This looks like a limitation that might push more experienced pros to choose the 10D despite its higher cost.) When shooting in Program AE, Shutter Priority, Aperture Priority, or Manual modes, the camera operates in AI Focus AF, meaning that it automatically flips between One Shot and AI Servo AF modes, depending on the subject. If the subject remains stationary, the camera remains in One Shot AF mode. However, if the subject begins to move, the camera automatically switches over to AI Servo AF and begins tracking the subject as it moves. This is a handy feature, letting you automatically track moving subjects without having to manually adjust the focus mode. When shooting in any of the Basic Zone exposure modes (Automatic or the preset scene selections), the 300D locks the focus mode to One Shot or AI Servo and doesn't switch between the two modes. The AF system's low light limit is EV 0.5, which combined with the AF assist lamp, provides excellent focusing in dim lighting conditions. Like the EOS 10D, the Digital Rebel 300D also offers what Canon terms "Predictive AF," which basically calculates the rate at which a subject is approaching or receding from the camera, and then accurately focuses based on the subject's predicted position. (A features that sports photographers will no doubt appreciate.)
The speed of the AF system is one of the areas in which the EOS 300D and EOS 10D excel over the relative to the system used in the D30 and D60 models. Canon rates the performance of their AF systems by the point at which they cease to be able to track an object moving at a constant speed toward the camera, using a given lens. The closer an object gets, the more rapidly the focusing point will change, so minimum focusing distance at a constant approach speed does provide a good measure of AF speed. While I don't have explicit performance numbers for the Digital Rebel, Canon tells me that it uses the same AF system as the 10D. Using Canon's EF 300/3.8 IS USM lens as the basis of comparison, the EOS 10D can track an object moving at 30 mph (50 kph) down to a minimum distance of 26.4 feet (8 meters). Under the same conditions, the D60 would lose focus tracking at a distance of 39 feet or 12 meters. Thus, by this measure, the EOS 10D's AF system is half again as fast as that of the D30 and D60 before it.
Manual focus is also available with any of the Canon EF lenses, simply by sliding the AF/MF switch on the lens barrel. The new EF-S lens also features the same switch, making it easy to quickly jump into manual focus mode.
AF-Assist Illuminator
Like the EOS-10D, the Digital Rebel uses the built-in flash head as its AF-assist illuminator, rather than a bright light built into the camera's body. This works quite well (as you'd expect, the flash is quite bright, and probably has a longer range than an on-body illuminator bulb), but has one serious drawback: The AF illuminator isn't available unless you're using the flash! For available-light photography, there doesn't seem to be any way to turn off the flash for the main exposure, yet still be able to use it as an AF-assist illuminator. For anyone doing a lot of available-light photography, this is a significant limitation. If you attach a 550EX external flash unit to the 300D though, its internal infrared AF-assist illuminator will operate without the flash being enabled, providing a useful working range of about 50 feet. For non-flash photography, Canon's ST-E2 wireless sync transmitter can also be used for AF assist, a handy trick. The ST-E2's AF-assist light has a useful range of about 25 feet.
Everyone understands that lenses sometimes get dust on them and need to be cleaned, and there are a lot of lens-cleaning cloths, solutions and other accessories on the market that work well. BUT, what do you do when your sensor gets dusty? Dust specks on the sensor tend to show up when shooting at very small apertures, appearing as dark blobs on your images. They're distracting at best, a terrible nuisance at worst, if you end up having to retouch every image to rid of them.
Most of us are naturally leery about the idea of poking around inside the delicate innards of our d-SLRs to wrestle with recalcitrant dust specks. Gently blowing the sensor surface (actually, the surface of the anti-aliasing filter) with compressed air gets rid of some dust, but there's invariably a lot that just stays stuck, no matter what. So what do you do?
If you've got dust specks on your sensor (and sooner or later you will), you're going to need to clean it. There are a lot of products out there intended to address this need, but a distressing number of them work poorly (if at all), and many are grossly overpriced. Advertising hype is rampant, with bogus pseudo-scientific jargon and absurd product claims run rampant. And prices - Did I mention prices? How about $100 for a simple synthetic-bristle brush?
So how do you know what product to use?
We don't pretend to have used everything currently on the market, but can tell you about one solution that worked very well for us. The "Copper Hill" cleaning method is straightforward and safe, and in our routine usage here at Imaging Resource, highly effective. Better yet, the products sold by Copper Hill Imaging are very reasonably priced. Best of all, Nicholas R (proprietor of Copper Hill) has put together an amazingly detailed tutorial on sensor cleaning, free for all.
Sensor cleaning is one of the last things people think about when buying a d-SLR, but it's vital to capturing the best possible images. Take our advice and order a cleaning kit from Copper Hill right along with your d-SLR, so you'll have it close at hand when you need it: You'll be glad you did!
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