Not just for birds. The RF 100-500mm L is good for long range landscapes and cityscapes.
Canon has a long history of being market leader in the realm of big (off)white L designated telephoto primes and zooms for professional and serious enthusiast sport and wildlife photography. These lenses have featured the best optics, electronics, image quality, focus, weather resistance and durability possible at the time of release.
By the way these lenses are near-white because light colored objects do not get as hot in the sun as dark objects. This matters because an increase in temperature of the lens could affect its optical properties due to expansion of the housing or the glass elements.
When Canon introduced the new mirrorless RF mount in 2018 they set about re-designing the classics and staples of the Canon catalogue. In many cases they sought to improve on the erstwhile EF lens with better optics, communication with the camera, autofocus, focal length range, performance or all of the above.
The predecessor of the RF 100-500mm is the well regarded EF 100-400mm L which was introduced in 2014.
The RF 100-500mm improves on the EF 100-400 with a longer focal length range and reduced mass. It has a different optical formulation without any fluorite elements , taking into account the reduced flange-back distance and benefits from the increase in electrical contacts from 9 to 12, seen on all RF bodies and lenses.
Unfortunately the initial rollout of the RF 100-500 L was somewhat blighted by several problems. Lens Rentals reported some copies with a cracked forward focussing element.
By the way apart from the mystery cracked element Lens Rentals commented very favourably on the RF 100-500, saying “..It’s a very well built and sturdy lens with cutting edge technology”.
Optical Limits reported autofocus problems on an EOS R. There have since been firmware updates to both the EOS R and the lens which have presumably solved the focussing issue, and I have heard no more about the cracked focus element so presumably Canon has fixed that.
On top of that, the lens was released in the middle of the Covid-19 pandemic which adversely affected supply chains. As a result the lens has been in very limited supply or unavailable around the world for many months.
Maybe Canon used the delayed roll out to ensure they fixed the problems seen on the first batch.
Anyway, I eventually located a vendor in Sydney which actually had one in stock and after parting with enough funds to buy a used car I finally got one in my hands.
I immediately photographed my standard test chart and a few birds around the house. I was amazed at the ability of the lens to reproduce very fine subject details even at a great distance from the camera.
Block diagram for Canon RF 100-500mm L.
Who’s it for
Professional and enthusiast Canon EOS R system users wanting a high grade tele zoom lens for sport, wildlife, birding and similar and who are prepared to live with the size, mass and cost of the lens to get the results they seek.
This lens cannot be mounted to Canon EF, EF-S or EF-M mount DSLRs.
Description
This is a typical Canon L superzoom, built to the highest standards of lens making. It is quite large, solid, a bit heavy to hand hold for long periods ( 2.35 Kg on an R5) and very well put together. It comes with reversing hood, rotating tripod foot which doubles as carry handle, zoom ring, zoom stiffness adjustment ring, focus ring, control ring, focus limiter switch, AF/MF switch, Stabiliser ON/OFF switch, and Stabiliser mode switch (1 for still subjects, 2 for panning, 3 for irregular movement).
Length with 77mm filter and front cap is 223mm. Total length fully zoomed out with the hood attached is 368mm.
Inside there are 20 elements in 14 groups, two focussing groups and one stabiliser group.
Capability
The focal length range of 100-500mm is very versatile, enabling the lens to be used for close action sports, open field sports, wildlife and birds.
The lens works well with the latest Canon mirrorless bodies to deliver fast reliable capture in a wide range of conditions.
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This is a 20Mpx crop of the original frame |
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This is a 0.4 Mpx crop of the surfer photo. You can easily read the time on her watch. I am on the beach, she is out there in the surf moving fast and still the lens can reveal this much detail. |
Focus
Arthur C. Clarke is often quoted as having said that ..”Any sufficiently advanced technology is indistinguishable from magic”.
I can tell you that with animal (includes birds) or human eye detect enabled the autofocus which this lens delivers on the EOS R5 is little short of magic.
It can detect and focus on a birds eye and keep tracking on the eye even when I would not have thought it possible to do so.
You have to experience this to believe it.
Otherwise all the usual autofocus modes work in exemplary fashion, fast and accurate with both one shot and AF servo.
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On the R5 body I find the RF 100-500mm L gives me a higher keeper rate than other lenses such as the RF 600mm f11 and the EF 70-300mm. |
Close focussing
Most very long lenses are unable to focus close. However the RF 100-500 L has two focus groups enabling it to focus down to 0.9 meters and to deliver magnification of 0.33x at the long end. This close focus ability can be very useful for capturing static subjects like flowers and also for birds which sometimes come quite close.
Teleconverters
The lens is compatible with the RF 1.4x and 2x converters although the focal length must be set greater than 300mm to enable the converters to be mounted.
I have not yet tested these.
Aperture
The aperture range is f4.5-7.1. People coming from the DSLR world sometimes wonder if the f7.1 aperture is compatible with fast AF. Not to worry, it is.
Canon dual pixel AF can in fact focus at f22 if required.
Stabiliser
Canon makes some rather bold claims for the effectiveness of its RF lenses with or without IBIS.
The way I test stabiliser effectiveness on the RF 100-500 is to set the zoom at 500mm and photograph a page of print about 6 meters from the camera hand held at shutter speeds 1/640 sec down to 1/10 sec in 1/3 EV step increments. I make runs with the stabiliser on and with the stabiliser off.
I find that with the stabiliser on (both the lens IS and camera body IBIS are automatically activated) I can get sharp pictures at a shutter speed on average about 3.5 EV steps slower than I can manage with the stabiliser off.
In fact I get this result for every RF lens I have tested on the EOS R5.
An advantage of 3.5 EV steps is certainly worth having and in fact with modern high pixel density sensors is pretty much essential for best results hand held. But it is not even close to the 6-8 EV steps claimed by Canon. I wonder how they derive that figure ?
Bokeh
Very nice, very smooth. No problems here.
Flares
The lens is somewhat flare prone with the sun at or near (inside or outside) the frame boundary. I use the hood at all times outdoors.
Sharpness and contrast
When I looked at my first shots I was blown away by the level of sharpness, resolution, contrast and acuity which this lens can deliver with good technique. Further use has only confirmed my initial impression.
The lens delivers excellent to outstanding sharpness across the frame from center to corners at every focal length and aperture up to f11 and is very good even at f16.
My copy shows no apparent decentering at all.
Color fringing, distortion, and peripheral shading are negligible with the lens profile in Lightroom or Camera Raw applied.
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You won't be inconspicuous with this lens in hand |
Alternatives
All the alternatives at this point are EF mount DSLR lenses which can be mounted on Canon RF bodies with an adapter.
Prices listed are in Australian dollars from a Sydney vendor GST paid.
The RF 100-500mm is currently selling for $4989.
From Canon we have the EF 100-400mm , a well respected lens with a good reputation. $3389.
From Sigma we have the 150-600mm, $1275 and the 100-400 for $1429.
From Tamron we have the 150-600mm for $1348 and the 100-400mm for $1249.
So the RF 100-500mm is around four times the price of two of the alternatives.
I have not used any of these so cannot comment on whether they represent good buying.
However I just note that the technical details of Canon lens mount and autofocus operation is not open which means that third party makers have to figure it out for themselves, not always with optimal results with respect to focus speed or accuracy. In addition Canon often offers firmware updates for both bodies and lenses to make sure they communicate properly. Third party makers often lag far behind with updates.
Just for some perspective on the matter of price, the recently announced Canon RF 400mm f2.8 is listed for pre-order at AUD19,379 and the RF 600mm f4 at AUD21,149.
Conclusion
The Canon RF 100-500mm L is probably the best lens I have ever bought, owned and tested in my 68 years of involvement with cameras and photography.
I rate it as excellent on all aspects of performance and capability.
It has no significant faults or failings that I have been able to detect.
Very highly recommended