Canon is reaching for the stars with its latest DSLR. Based on the acclaimed 20D, the new 20Da has been designed for use by astrophotographers, with the incorporation of new features tailored specifically to their needs. These include innovations such as a live preview on the LCD monitor and a modified low-pass filter optimised for photographing the night sky. Canon claims that the latter 'yields sharper and higher contrast images of various astronomical phenomena such as diffuse reddish nebulae. The modification increases the transmission of light at the wavelength of 656nm, known as the Hydrogen Alpha line, by a factor of 2.5x compared to the standard EOS 20D digital SLR.' Canon has overcome the technical problems in incorporating a live preview into an SLR (due to the mirror and shutter mechanism) by locking up the mirror and opening the shutter to display a magnified live view of the subject on the 1.8" LCD screen, though this can only be done at night. The live preview can also be viewed on a TV via the camera's Video Out terminal. The 20Da also features an enhanced noise reduction algorithm optimised for the long exposures necessary in night photography. Like the 20D, which will continue to sit alongside it on the shelf, the 20Da is compatible with all Canon EF and EF-S lenses and can also attach to a telescope, via a T-mount. It will be available from mid-July 2005 for £1,829. 99 RRP inc. VAT from selected specialist dealers. Visit www.canon.co.uk or phone 08705 143723 for more information.