The EOS 1D Mark IV, which Canon presented to BJP in an exclusive briefing ahead of its announcement, sports a 16.1 million pixel resolution APS-H-sized sensor that has been 'designed, developed and manufactured in-house,' says Mike Owen, Canon's team leader in the DSLR product planning division. The camera offers a 1.3x crop factor, which gives leeway to photographers without compromising on image quality, claims Owen.

As with its predecessor - the 1DMark III - the new model offers a burst rate of 10fps at full resolution with a 14-bit conversion rate. However, its buffer has been increased allowing for continuous shooting of up to 121 JPEG files and 28 raw images, a 10% increase over the 1D Mark III.

The 1D Mark IV now offers a wider standard ISO range from 100 to 12,800. Photographers can also boost the initial setting up to ISO102,400 - matching the Nikon D3s - and down to ISO50. 'We now have the widest ISO range on the market,' claims Owen.

The camera's autofocus system has also been reworked while keeping the same design. 'It's a brand new 45-point AF sensor,' says Owen. 'All 45 points are selectable and 39 of those are cross-type points.' The autofocus system has a dedicated microprocessor, and similarly to the 7D camera, spot-AF is now available. Different AF points can also be set for vertical or horizontal orientation, so photographers can automatically switch between landscape and portrait shots without touching a button, says Canon. 'This should be very popular with sport photographers,' Owen tells BJP.

Canon also claims to have learnt from its previous mistakes regarding the autofocus system. Weeks after the release of its 1D Mark III camera, photographers reported issues with the camera's sub-mirror, which caused autofocus tracking inconsistencies when used in Artificial Intelligent Servo continuous shooting mode (BJP, 07 November 2007). 'According to the feedback we've received from early users, these concerns have been resolved,' says Owen. 'We've learnt a lot with the 1D Mark II and Mark III, and all that learning has been implemented in this product. We're confident that it will fill photographers' requirements.'

Canon has also introduced a full HD movie mode to the pro photography range of DSLRs. 1D Mark IV users can now shoot full resolution 1080p HD movies at three different frame rates - 24, 25 and 30fps. A 720p movie mode is also available at 50 and 60fps, which will allow for slow motion video shooting, says Canon. Photographers can also grab stills from the movies, but not in-camera, Owen confirms.

The camera's LCD screen has also been improved. The three-inch Clearview II LCD screen is similar to the 7D's, with 920,000 pixels. 'However, it has a new solid structure to prevent glare in all situations,' says Owen.

Like its predecessor, the 1D Mark IV is weather proofed. It has 76 physical seals, and is entirely secured when used with water-resistant EF lenses. Canon has also improved the camera's buttons, which now offer clear feedback when pressed.

The 1D Mark IV also includes Canon's auto-lighting optimiser, intelligent noise reduction, live view, which was first introduced in the 1D Mark III, and the EOS automatic cleaning system.

'We feel that the 1D series has been the benchmark for working in harsh and difficult conditions,' Owen tells BJP, 'and we had to continue this. It's more than just a set of specifications. It is about what all of these bring together to the photographer. The 1D series has to embody speed, performance and reliability. It has to react as quickly as a photographer's mind. While people had issues with autofocus in the past, the image quality was always very well received. And, this is what we had in mind with the 1D Mark IV.

The 1D Mark IV will be compatible with its predecessor's wide range of accessories, including its batteries. It will be available in December, retailing at around £4500. It will be released alongside a new Wireless File Transmitter - the WTF-E2 Mark II, which is now 802.11 a/b/g compatible and can link to GPS via a Bluetooth dongle. The new transmitter will retail at approximately £700.

For more details, visit www.canon.co.uk.

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