Canon RF 600mm f/11 IS STM: The Diminutive Giant
The Canon RF 600mm f/11 IS STM is retractable and small, portable and light, and surprisingly inexpensive for its focal length. K Madhavan Pillai discovers more.
Canon is certainly sweetening the deal for RF-mount camera owners and prospective buyers. Announced in July 2020, the RF 600mm and RF 800mm (both with no aperture diaphragms within the lenses, with aperture values fixed at f/11) was intriguing, to say the least. There are some big benefits in having a fixed focal length and aperture. Optics can be simplified and designed for performance. Blurs and bokeh is optimised by the perfectly circular aperture. The lens can be made smaller, lighter and designed to be portable.
Contributing to the reduced size is a collapsible or retractable barrel-in-barrel design, along with a distinct but simplified optical layout that Canon has been perfecting for decades. The Canon RF 600mm f/11 IS STM uses gapless dual-layer diffractive optics instead of multiple heavier individual elements, which also controls fringing, aberrations, and fl are. An STM stepping motor delivers quick, quiet AF, suitable for both stills and video. It also allowing full compatibility with the RF 1.4x and 2x extenders, for an effective focal length of 840mm or 1200mm, respectively. There is an AF range limiter switch that locks out the closer focusing range between 4.5m (or 14.75 feet, a modest closest focus distance) and 12m, to speed up subject acquisition at longer distances.
A ‘clicked’ control ring on the lens can be customised for a variety of settings (ISO, shutterspeed, compensation, Picture Style, white balance, AF mode, flash EV). Focusing is internal, allowing the use of linear polarisers or graduated filters. The 82mm filter size is convenient and useful. The optical stabilisation, especially useful at 600mm, is rated for five stops.
The lens is made of engineering composite plastics and moulded resin. The locking mechanism, rings and switches are well implemented, and feel sturdy.
The retractable design makes the RF 600mm f/11 extremely compact and easy to carry. Weighing just under a kilo, with the lens extended and locked at the shooting position, the lens is fantastically convenient to move and position on a bean bag, tripod, or even use handheld. On a tripod, the lack of rotatable collar will necessitate a suitably sturdy pan/tilt head. Unfortunately, there is no weathersealing, making it imperative to use this lens carefully, and wipe away any moisture or dirt on the barrel before retracting the lens after use.
Because of the fi xed f/11, AF points function within a square that covers about 50 percent of the frame at the center. But this would work with extenders too. This lens is best suited to the EOS R6, with its newer sensor, better AF especially in low light, and leading noise performance at higher ISO settings. Despite this, f/11 makes low light photography considerably more challenging. And, f/11 also means ramping up the ISO to 6400 or greater, in daylight, when higher shutterspeeds are needed, especially when subject motion needs to be frozen. This given, the RF 600mm will function perfectly well on any EOS R series body, including the lower priced EOS RP.
The RF 600mm f/11 shows impressive optical characteristics, with good sharpness across the frame, and minimised aberrations. AF is satisfyingly speedy, quiet, and responsive for most situations, but expectedly, it begins to hunt when light levels get below a certain threshold. For an ultra-telephoto lens at its price, it went beyond my expectations in performance.
At Rs 63,995, the Canon RF 600mm f/11 IS STM is a veritable fraction of the price of Canon’s 600mm f/4. Canon is certainly breaking down the entry barriers to ultra telephoto lenses. While there are some challenges in using a lens with a constant f/11, there are also some extraordinary benefits—size and portability, coupled with excellent optical performance. I see its primary use for wildlife enthusiasts and birders, but it gives itself well to all forms of photography. Well recommended.
This article originally appeared in the April 2021 issue of Better Photography.
600mm with fi xed f/11, silent stepped AF, IS, 82mm fi lter diameter, excellent price
Good sharpness, responsive AF in good light, hunting in low light, minimal aberrations
Resin and sturdy plastics, no weathersealing
Retractable design, ultra-portable 600mm
|Warranty & Support
Two year warranty, good service
|VALUE FOR MONEY||4.5/5|
|Who should buy it?||Wildlife enthusiast and birders who cannot afford the large aperture version.|
|Why?||Well-designed, with good ergonomics on mirrorless bodies, this lens has fast AF, and has excellent performance.|