Canon has today announced two new Image Stabilized EF-S lenses. Utilizing an all new and considerably simpler stabilizer system these two lenses are virtually the same size and weight as the lenses they replace / upgrade. These two lenses in a 'combined kit' form would provide you with approximately 28 to 400 mm equiv (14.3x) field of view, with image stabilization, on an EF-S compatible Canon digital SLR (such as the Digital Rebel XTi / EOS 400D). No word on price for the 55-250 mm IS at this point but the 18-55 mm IS should be $199 when it arrives in October.
Phil: This new IS system appears to be based on some kind of analogue feedback system, although obviously Canon aren't revealing exactly how it works the diagrams found below tell some of the story. We are told this new IS system is just as effective as the existing Canon optical IS systems.
Canon expands EF-S range with two new lenses
Amstelveen, The Netherlands, 20 August, 2007: Canon today strengthens its EF-S series of lenses with the launch of the EF-S 18-55mm f/3.5-5.6 IS and EF-S 55-250mm f/4-5.6 IS. With equivalent focal lengths of 29-88mm and 88-400mm respectively, the lenses are the first in the EF-S series to incorporate a 4-stop Image Stabilizer, dramatically extending low-light performance. Both lenses incorporate specialist optics to achieve exceptional image clarity - the EF-S 18-55mm f/3.5-5.6 IS employing an aspherical lens element with the EF-S 55-250mm f/4-5.6 IS benefiting from an Ultra-Low Dispersion (UD) lens element.
The lenses are built to fit exclusively on those EOS cameras with an EF–S lens mount – including the new EOS 40D, EOS 30D, EOS 400D and earlier models.
EF-S 18-55mm f/3.5-5.6 IS
The EF-S 18-55mm f/3.5-5.6 IS is a lightweight general-purpose zoom lens that is ideal for handheld photography in a wide range of lighting conditions. Offering high optical quality, the lens has an 11 element, 9 group construction, including one aspherical element for crisp corner-to-corner detail. The lens maintains a closest focusing distance of just 25cm throughout the zoom range, giving photographs the flexibility to frame up close when needed.
EF-S 55-250mm f/4-5.6 IS
Compact and lightweight, the EF-S 55-250mm f/4-5.6 IS offers the longest zoom range in the EF-S series to date. The 88-400mm equivalent focal length opens up new framing possibilities for owners of EF-S mount cameras shooting wildlife, sports and travel photography. Optical quality is assured through a UD element, which minimises chromatic aberrations that could otherwise cause reduced contrast and colour fringing.
4-stop Image Stabilizer
Canon’s latest optical Image Stabilizer (IS) technology provides up to 4-stop compensation for image blur caused by camera shake and slow shutter speeds. Photographers normally shooting handheld at 1/250 sec can switch on IS to obtain a similarly steady and blur-free result with a shutter speed of just 1/15 second. The inclusion of automatic panning detection makes it easier for photographers to track wildlife and other moving subjects. To ensure consistently accurate results at all zoom positions, the IS system within each lens has been optimised for that lens’ specific focal length range. Since the IS system is based within the lens, the results are visible through the viewfinder when framing the image.
(Phil: Below is a diagram of the IS unit from the 70-200 mm F2.8L IS lens for comparison, as you can see the new design is considerably simpler and is said to be just as effective).
Appealing background blur
Both lenses also incorporate a circular aperture. This helps create an even background blur when depth of field is minimised, giving photographers more creative options for portraiture and similar types of photography.
Super Spectra coatings
Both models employ Canon’s patented Super Spectra coatings to suppress flare and ghosting – more prone to occur with digital cameras due to reflection off the image sensor. By increasing light absorption, coatings reduce reflections off lens element surfaces to deliver crisp, undistorted images with natural colour balance.
E-TTL II flash integration
The lenses transmit distance information to the E-TTL II flash system of all current model digital EOS cameras, improving flash exposure metering when used in conjunction with Canon’s range of EX Speedlite flash units.
In keeping with Canon’s Kyosei philosophy of living in harmony with the environment, the lens features only lead-free glass.