- L-series telephoto lens
- Four-stop Image Stabilizer to help prevent blur
- Three IS Modes
- Power Focus mode
- Fluorine lens coating
- Two Fluorite lens elements reduce chromatic aberration and colour blurring
- Robust, but lightweight, build with superb handling
- Close focusing distance of 4.5m
- Ring-type USM with high-speed CPU for silent, high-speed AF
- Security cable lock attachment point
- Long and short tripod attachments plates provided
- Only lead free glass used in construction
The older EF600mm f/4L IS USM is a very well respected lens that produces high quality results in a wide variety of situations. The new lens takes these qualities and improves on them in all areas to produce a professional lens able to create high quality results in all situations.
With the use of 16 lens elements in 12 lens groups, as well as two Fluorite lens elements, it effectively minimises chromatic aberration and eliminates colour blurring around the edges of a subject providing higher levels of resolution and contrast than the outgoing model.
The optical design and the placement of lens elements as well as the use of a SubWavelength Structure Coating (SWC) on some of the lens elements reduces ghosting and flare when a bright light source is included within the frame.
The lens' ring-type USM autofocus motor combines with an optimized AF algorithm to provide autofocus on par with the outgoing model. The new Power Focus mode is activated from the focus mode selector switch. This mode allows the lens to adjust the focus smoothly by driving the AF motor. It can be used when shooting movies with the lens to provide a pull focus effect. Power Focus is activated by turning the focus preset ring. A small turn will drive the focus slowly, while a larger turn will provide a faster movement through the focus range.
In a serious effort to improve the handling of the lens, the size and weight have been reduced and the focus ring and switches have been redesigned and repositioned. The weight reduction is 1.4kg (down to just 3.92kg from 5.36kg) compared to the previous 600mm lens and has been made possible by the use of magnesium alloy and titanium in the lens body construction. This weight saving of 27% frees the lens from always being tripod mounted and makes it possible to hand-hold, being as it is, just 50g heavier than the older EF500mm f/4L IS USM lens.
Photographers who may previously have looked at the EF600mm f/4L IS USM lens but decided to go for the EF500mm f/4L IS USM lens instead, now have the option of gaining the extra 100mm focal length for no appreciable gain in weight. For anyone that travels by air, this will be a major benefit.
The focus ring has been moved to fit in a more ergonomic position and it has been made wider so it is easier to find when your eye is at your camera's viewfinder. The switch arrangement has also been modified. The switches are now less likely to be knocked accidentally, and the arrangement is such that the most commonly used switches are placed closer to the camera body, while those used less frequently are placed further away.
Improved durability is another area that has been addressed. The new lens features better dust and moisture proofing and a more durable IS mechanism to ensure it keeps working in all environments.
To help limit the risk of theft, the tripod collar-locking knob features a security attachment point compatible with Kensington-type cable locks. By attaching a cable lock to the locking knob rather than the lens itself, the lens can still be rotated within the tripod collar without tying the lens up in the cable lock.
Designed with lens extenders in mind, the EF600mm f/4L IS II USM lens functions perfectly with the Canon's Mark III Extenders to still provide exceptionally high image quality and extra reach. With the EF1.4x III Extender you'll achieve a 840mm f/5.6 focal length and with the EF2x III, 1200mm f/8. With the EF1.4x III Extender AF and IS will function with all EOS models. With the EF2x III Extender AF will function at the central focusing point with the EOS 3 and all EOS-1 series models since the EOS-1V. IS will function with all cameras since the EOS 500. To get the best performance out of the new lens with the Mark III extenders, ensure that you always attach the Extender to the lens first, before attaching the whole unit to the camera. This ensures that the (combined) lens information is transmitted correctly to the camera body to provide the optimum image quality and focus performance.
A ring-type USM autofocus motor, combined with a high-speed CPU and optimised AF algorithm, delivers fast and near-silent AF with precision. It also provides full-time manual focus so that you can adjust the focus with the focus ring, without first having to switch the lens to manual focus. This allows you to adjust the focus accurately to ensure it is exactly where you want it to be for the most creative control possible.
The addition of Power Focus mode allows you to activate a motor driven focus shift for use when shooting movies enabling a smooth transition between focus distances. It is activated by the knurled focus recall switch found between the focus ring and the AF Stop button ring.
The Image Stabilizer in a Canon lens works by shifting a stabilizer group of elements to compensate for motion detected by a gyroscope in the lens. There are now three IS modes – Mode 1 for general shooting, Mode 2 for panning and Mode 3 which is ideal for sports photographers.
The panning mode, Mode 2 features a modified IS algorithm as well. This new algorithm negates the IS ‘bump' that can occur when you first start panning the lens providing a more stable viewfinder image. The new IS mode, Mode 3, only activates the IS mechanism when you full depress the shutter button to shoot an image. For sports photographers moving between shots, this avoids the lens trying to stabilize random, rapid movements and only begins to compensate while you are shooting.
Once activated, the Image Stabilizer gives up the equivalent of four stops of shutter speed so you can handhold and capture acceptably sharp images at much slower shutter speeds.
For movie shooting with a tripod, the IS mechanism can be left switched on. The lens will detect it is mounted on a tripod and the IS optics will be locked in place so they cannot move. If vibration is detected the IS will then activate to remove vibrations.
Keeping lenses clean is important to ensuring the best image quality possible. To help with this, both the front and rear lens element are coated with fluorine which acts as a non-stick, easy to clean surface to help with the removal of dust and dirt or oils left by fingerprints or from the atmosphere. Fluorine is also used on the filters covering the CMOS sensor camera and the rear LCD panels of several EOS models for the same reason.
SubWavelength Structure Coating
Designed for use in digital photography, Canon's patented lens element coating helps to prevent the ghosting and flare caused by internal reflection - helping to deliver crisp, clear images. The EF24mm f/1.4L II USM was the first Canon lens to feature the SubWavelength Structure Coating and it is now found on several lenses in the range. This coating reduces reflection from the surface of the lens - it has the advantage of reducing both flare and ghosting to improve image quality.