Canon RF 100-500mm Review: A Wildlife Photography Field Test

In this article, we’ll be looking at the Canon RF 100-500, a lens well-known in the wildlife photography world as an all-rounder.

We’ll be putting this lens to the test in the field and examining some of its most important qualities, such as its handling, image quality, low-light capability, and more.

Read more: What’s the Best Lens for Wildlife Photography

A personal perspective

I am a wildlife photographer, and for several years, I have been using my 600mm f/4 prime lens for most of my wildlife photography.

However, throughout my career, I have occasionally been lucky enough to have interactions with animals that were not too shy. These moments allowed me to get quite a bit closer to a species, and for them, my 600mm focal length was too much.

I used to use a 70-200 f/2.8 for these situations; however, I found that often it was a bit too short – there was too much of a gap between my 200mm and 600mm lenses. Additionally, there were some occasions where it was simply not possible to bring a big and heavy 600mm lens.

I therefore became very interested in the Canon RF100-500mm f/4.5-7.1 L IS lens. It was lightweight, promised excellent image quality, and seemed to be very versatile.

I bought the lens two years ago and have used it for a variety of subjects on different continents, and I am happy to share my thoughts on it here.

Build, handling, and economics

One of the most exciting things about the RF100-500 is its small size and lightweight design for a lens that can reach up to 500mm.

At around 1.53 kg, it’s easy to handhold even over longer periods of time, and if you remove the tripod collar (as I did), you can get the weight down to 1.37 kg. With a length of 20.8 cm, it also easily fits in most photography bags.

The lens is an external zoom, meaning that the barrel extends when zooming in. I have had no problems with weather sealing so far.

It is worth noting, as with most external zooms, that zooming from wide to far requires a larger turn of the zoom ring, which can be a disadvantage if you need to zoom in or out very quickly.

The minimum focusing distance is 0.9m at 100mm and 1.2m at 500mm, resulting in a maximum magnification of 0.33x. If you plan to photograph shy birds or larger mammals, this may not be relevant for you.

But if you also do some occasional macro photography of dragonflies, amphibians, or flowers, you might be surprised how well the lens works for these subjects.

I also learned to appreciate the short minimum focus distance for taking pictures of hummingbirds at a feeder or for capturing portrait shots of birds in a local park.

There are some things I have become aware of that are worth knowing:

The lens is equipped with four rings: the lens control ring, the focus ring, the smooth-tight ring, and the zoom ring (from back to front). The smooth-tight ring allows you to adjust how easily the zoom ring can be rotated.

Unfortunately, the smooth-tight ring has shifted position on me before being packed into a backpack. I have never used the control ring, as I find it very hard to reach, and I would have preferred to have it in front of the smooth-tight ring.

Additionally, the coating on the front element doesn’t seem to be very scratch-resistant. Even though I treated the lens carefully (or at least as carefully as I treat my other lenses), I noticed a few small scratches. I have heard of similar experiences from other photographers.

Image quality and extenders

The lens delivers excellent image quality that is basically on par with many prime lenses, even when shot wide open. It can be used with both the 1.4x and 2x extenders. I have mainly tried it with the 1.4x extender and was still very happy with the image quality.

However, there are some important restrictions when using the extenders. Due to the design of the extenders and the position of the back element on the RF 100-500, extenders can only be used from 300mm on.

This results in a 420-700mm or 600-1000mm lens, respectively. This can be a bit cumbersome when mounting the extender, and if you have a small backpack, the lens might not fit anymore due to the drastically increased length.

The 1.4x extender works well for occasional use, but I would not buy the 2x extender for this lens as both autofocus and image quality take a hit. If you think you will often need more than 500mm of focal length, then I would recommend having a closer look at the RF 200-800 f/6.3-9 lens.

Autofocus

The RF100-500mm f/4.5-7.1 L IS features a dual nano USM autofocus motor, and it is probably the fastest focusing lens I have ever used.

It works great for a variety of subjects, including small birds in flight, where the light weight of the lens is a big advantage over a larger prime lens (such as a 600mm f/4).

Despite the relatively small maximum aperture of f/7.1 at 500mm, I had no serious issues when photographing in dark environments such as rainforests.

However, you can feel a drop in performance, and in these situations, I preferred my RF600mm f/4 L IS – even though autofocus was not the main reason.

Image stabilizer

The light weight and excellent image stabilizer make the lens an amazing option for handheld shooting. I have used it in tropical rainforests, and as long as the subject is not moving, the image stabilizer can make up for the rather slow aperture.

Even fully zoomed in at 500mm, I have managed to get plenty of sharp images at shutter speeds of 1/30 or even 1/20 sec.

Low-light capabilities and background blur

When the lens was announced, I was originally not sure if I should buy it, mainly due to the relatively slow aperture of f/7.1 at the long end. If your subject is not moving, you can decrease your shutter speed, but what if you want to take some action shots in a forest or on a rainy day?

In these situations, you are forced to use rather high ISO, but I feel that with a modern full-frame camera and AI-based noise reduction tools, the RF100-500 performs quite well in low light.

For me, the bigger downside of the f/7.1 aperture was the relatively large depth of field, which can make it hard to get a smooth background in some situations.

If you are in a situation where the background is relatively calm (e.g., when photographing shorebirds on a beach), this was rarely an issue.

For small subjects, such as small passerines or hummingbirds, the background blur was often also sufficient, even when not shooting at a feeder or other setup.

Where I struggled most was when I tried to achieve a smooth background for larger animals, such as storks, herons, or deer. In those situations, a fast prime such as a 400mm f/2.8 or 600mm f/4 would be my lens of choice.

In conclusion

After using this lens for more than two years, I consider the Canon RF 100-500 f/4.5-7.1 L IS lens a pretty perfect all-rounder for wildlife photography.

It can be a great lens for photographers who want to take wildlife photography more seriously or those who are looking for a flexible zoom lens that complements their big 500/4 or 600/4 prime.

It also works great for occasional macro photography or capturing landscape details. However, if your work tends to revolve more around shy and elusive animals that will often be at a great distance from you, the RF 200-800mm f/6.3-9 IS might be a better option to consider.