Announced concurrently with the EOS R5 and EOS R6 cameras are two ground-breaking, lightweight and affordably-priced super telephoto RF lenses for enthusiast photographers.

Canon’s new RF 600mm f/11 IS STM (top) and RF 800mm f/11 IS STM lightweight super-telephoto lenses. (Source: Canon.)

Both lenses are significantly smaller, lighter and cheaper than existing Canon EF super telephoto lenses – as well as being much more affordable.  The RF 600mm f/11 IS STM weighs approximately 930 grams, while the RF 800mm f/11 IS STM is approximately 1,260 grams. Minimum focusing distances are 4.5 metres for the RF 600mm f/11 IS STM and 6 metres for the RF 800mm f/11 IS STM (the same as for the EF-mount equivalent lenses). Both are compatible with the new Extender RF 1.4x and Extender RF 2x teleconverters (see below). We’ve been told the RRPs for both lenses will be ‘under AU$2000’ when they go on sale at the end of this month.

This illustration shows the RF 600mm f/11 IS STM lens in use. (Source: Canon.)

Both lenses come with built-in optical Image Stabiliser technology and support Dual Pixel CMOS AF when paired with a Canon EOS R System mirrorless camera. Using Diffractive Optics, combined with the RF Mount and a fixed f/11 aperture, both lenses have been developed to be used hand-held and are equipped with a retractable barrel structure that makes them easy to transport and store. Stepping motor (STM) focus adjustment makes autofocusing extremely quiet and very smooth while the Lens Control Ring on both models gives enthusiasts direct and speedy control over settings such as shutter speeds, exposure compensation or ISO sensitivity. The table below compares key specifications for the new lenses.

RF 600mm f/11 IS STM RF 800mm f/11 IS STM
Mount Canon RF
Focal length 600mm 800mm
Aperture f/11 (fixed)
Minimum focus 4.5 metres 6.0 metres
Depth of field at minimum focus 3 mm
Max, magnification 0.14x
Optical construction 10 elements in 7 groups, incl. one DO lens with gapless dual-layered diffractive optics 11 elements in 8 groups, incl. one DO lens with gapless dual-layered diffractive optics
Stabilisation Yes. 4 stops
Focus Drive Stepping Motor (STM) + lead screw
Filter diameter 82 mm 95 mm
Diameter 93 mm 101.6
Length (retracted)  Approx. 199.5 mm Approx. 281.8 mm
Length when shooting Approx. 269.5 mm Approx. 351.8 mm
Weight 930 grams 1,260 grams
Lens hood ET-88B (sold separately) ET-101 (sold separately)
Lens cap E-82II (supplied) E-95 (supplied)

Comment: Canon will probably attract some flak from the usual fanboys with more self-belief than expertise. The fixed f/11 aperture, in particular, is likely to be panned; yet it’s a logical decision by Canon and it enables the design to be optimised for high performance with minimal weight and production complexity – and huge weight and cost reductions. To provide some figures: weight-wise, the RF 600mm f/11 IS STM weighs 930 grams, compared with 3.05 kg for the EF 600mm f/4L IS III USM lens, while the RF 800mm f/11 IS STM weighs 1.26 kg, compared with 4.5 kg for the EF 800mm f/5.6LIS USM lens.

Cost-wise the difference is even more dramatic as we’ve been told the RRPs for both lenses will be ‘under AU$2000’ when they go on sale at the end of this month. Going by leaked US pricing, the RF 600mm f/11 IS STM could even be around AU$1000, while the RF 800mm f/11 IS STM may well be under AU$1500. In contrast, Canon’s online store has the EF 600mm f/4L IS III USM lens listed at AU$18,399 and the EF 800mm f/5.6LIS USM lens at $15,599. Those EF prices are well beyond the reach of most photo enthusiasts.

Photographers looking for shallow depth of field should not be disappointed with the new lenses, either, despite their fixed f/11 apertures. By our calculations, the depth of field at the shortest focusing distance (4.5 metres) with the EF 600mm f/4L IS III USM lens will be around three millimeters. Interestingly, it will be the same with the EF 800mm f/5.6L IS USM lens at its minimum focusing distance of six metres. At their maximum aperture settings and minimum focus distances, the equivalent EF lenses have one millimeter depth of field, which would provide significant focusing challenges.

It is well known that depth of field increases with distance from the camera for a given aperture. So with subjects at 10 metres from the camera, both the 600mm lenses at f/11 would have a depth of field of 18 cm; at 20 metres this increases to 76 cm and at 50 metres to 4.84 metres. With the 800mm lenses at f/11, these figures will be 10 cm, 42 cm and 2.71 metres, respectively because of its longer focal length.

This illustration shows the RF 800mm f/11 IS STM lens in use. (Source: Canon.)

To counter further uninformed criticism we’d like to stress that the designers of these lenses have taken advantage of features in the new EOS R5 and R6 cameras that reduce the need for very fast lenses.  They include:

  1. Both cameras’ EVF have high resolution and fast refresh rates and, as everyone should know, the brightness levels of EVFs are adjustable if you need more light to focus manually. (This wouldn’t be true had the lenses been made for DSLRs with optical viewfinders.)
  2. Autofocusing will not be difficult because the Dual Pixel CMOS AF II autofocusing systems in the new cameras can focus in light levels down to -6.0EV (with the R5) or -6.5EV (with the R6). They also claim lock-on times as brief as 0.05 seconds and the AF sensors cover the full image frame, enabling fast focusing even on subjects towards its edges. Tracking moving subjects should be relatively straightforward since face and eye detection algorithms include human face, eye and head detection plus the ability to detect the eye, face or whole body of animals like dogs and cats as well as birds.
  3. Improvements to noise reduction processing allow users to shoot with high ISO settings, enabling the camera’s top auto sensitivity to be set to at least ISO 6400, knowing it will still produce relatively noise-free images.
  4. Both lenses come with built-in stabilisation which provides up to four stops of shake correction, even on cameras without integrated stabilisation.

We’d also like to point out that both lenses address the needs of the current market for smaller, lighter and more affordable long-focal length lenses (something highlighted by DPReview on 1 July 2020) . For the past decade or so, buyers of interchangeable-lens cameras have tended to be mainly in the over-50 age bracket and many are aware of how heavy gear can limit the activities they can engage in. These lenses address the weight issue extremely well. We expect they will be sought-after, especially by birders who will be attracted by their range, stabilisation, near-silent operation and ease of use.

This illustration shows how the  is easily fitted into a regular camera bag. (Source: Canon.) 

In our opinion, the combination of weight, price and built-in stabilisation make Canon’s RF 600mm f/11 IS STM and RF 800mm f/11 IS STM as exciting as the company’s new R5 and R6 cameras. These lenses will bring telephoto shooting to a wide variety of photographers, ranging from parents who simply want to take pictures of their children playing sports through sports enthusiasts looking to get closer to the action for taking stills and recording movie clips and extending into entry-level wildlife photographers and anyone who wants affordable gear that won’t weigh them down. Add in travellers and you can see a large potential market for these lenses.

We expect they’ll be popular, particularly once COVID restrictions are eased. They are scheduled for local release on 30 July.

The new RF Extender 1.4x and RF Extender 2x teleconverters. (Source: Canon.)

Announced concurrently with the 600mm and 800mm lenses are the RF Extender 1.4x and RF Extender 2x teleconverters, which have been are designed for press, nature and sport photographers who want a lightweight an affordable way to extend the reach of the

RF100-500,  RF600 and RF800 lenses. Reliable and durable, these extenders match the performance of these lenses and use advanced high-refraction, low-dispersion glass to control curvature of field and chromatic aberration of magnification. They also feature an optimised lens coating and a three-layer combined lens to reduce ghosting plus a heat shield coating to prevent performance deterioration in high temperatures. Weather-resistant sealing is available when used with a compatible L-series RF lens. The table below shows the main specifications for the new extenders

RF Extender 1.4x RF Extender 2x
Mount Canon RF
Lens light fall-off One stop Two stops
Lens construction 7 elements in 4 groups 9 elements in 5 groups
Max. diameter 71.2 mm
Overall length 40.6 mm 60.6 mm
Weight 225 grams 340 grams
Compatible lenses RF 100-500mm f/4.5-7.1, RF 600mm f/11, RF 800mm f/11
Lens case LP811 (supplied)
Extender cap Extender cap EXTENDERCAPRF (sold separately)

Note: when used with the RF 100-500mm f/4.5-7.1 L IS USM, the zoom range is limited to 300 to 500mm when the extender is connected to prevent the lens’s rear elements from hitting those of the extender. Both extenders are due for release on 30 July.

Footnote: Canon has the RF 600mm f/11 IS STM lens available for pre-ordering at AU$1559 and the RF 800mm f/11 IS STM priced at AU$2030 but one of the few online retailers to have these lenses listed are showing selling prices of AU$1299 and $1699, respectively. Although these prices are higher than our original estimates, which were based on US prices, they remain significantly less than the prices of the equivalent EF lenses. We’ve also found the RF Extender 1.4x listed for pre-order at AU$999 and the RF Extender 2x at $1199 at a mjor Australian reseller.