More Thoughts But No Reflections — Taking Wildlife Photography Mirrorless

Richard George
9 min readSep 23, 2022

This is part 3 in a series consisting of “Some Notes on DSLR Wildlife Photography” and “Further Thoughts on DSLR Wildlife Photography”, updated based on my current kit and approach.

A slightly soft-focus image of a Philadelphia Vireo, a small songbird with a pale yellow throat and breast, blue-gray wings, back and head, and a striking white/black/white banding across the eye, perched on a twig in front of blurred foliage.
Philadelphia Vireo in soft focus

The above image is a reasonable example of where my photography is at now; it’s a quickly-taken opportunistic image that isn’t quite technically perfect (there’s something inherently soft-focus about Vireos), but still a pleasant and satisfying record of a lifer. At the time of writing it’s also my most recent lifer, my 195th in the USA, although I didn’t realize this at the time — I’d thought I was photographing a Warbling Vireo, a very similar (and more locally common) songbird that has slightly less bold markings, particularly a whiter breast, drabber back with less dark on the wing, and less dramatic eyelines. It’s a bird that’s almost unknown in the area except during fall migration in September, so one I’d have missed if I hadn’t gone out specifically to catch this birding period.

The kit used to capture the photo has changed too, which is my main reason for this update. I’ve switched from the EOS90D DSLR to a Canon R5 Mirrorless. I’d held off from this transition for some time as I was uncertain about mirrorless technology and didn’t really want a full-frame sensor, but its high specification and good reviews eventually overcame that.

DSLR vs Mirrorless technology

Before I go into the why/why not of the technical decision, a few notes on DSLR versus mirrorless. Both are a mid-size style of camera with typically very similar bodies and (often compatible) interchangeable lenses. Both usually have a viewfinder, an electronic back display, and a similar set of buttons, controls and menus.

The main difference is that in a mirrorless camera, there is no light path from the lens to your eye. The viewfinder is electronic — a tiny monitor — and therefore only works while the camera is on. That means you can’t, as with a DSLR, just swing it up and look through it without turning it on. This seems obvious but it’s still disconcerting to raise a camera to get a dark eyepiece, however quickly a button-press lights it up. It also means the power requirements, and battery drain speed, are a little higher.

There are of course benefits, not merely in mechanical complexity, or mirrorless cameras wouldn’t exist. For the birder, the main one is the silent operation. If you set a mirrorless camera to electronic shutter (there’s usually still a mechanical shutter present), nothing has to slam out of the way to take a shot. There’s no clattering for a subject to react to. There’s also the ability to show more image data in the viewfinder, and the fact that the viewfinder can be set to simulate your current exposure, letting you know if an image will be incorrectly exposed before pressing the shutter. Further, the fact that light is constantly hitting the full sensor allows for considerably more flexibility and accuracy in autofocus modes.

The other main difference between the 90D and R5 is that while the R5 has a “full size” image sensor (the same size as a 35mm film negative), the 90D’s is “cropped”, with a crop factor of 1.6. A “crop sensor” is one that covers a smaller area within the 35mm footprint, so its images come pre-cropped to that smaller area. The benefit of this smaller image area is that the camera magnifies that smaller part of the lens’ field of capture, making your lens an effective factor of 1.6 longer, at the cost of some technical limitations on the smaller sensor. So switching to a full sensor would mean my lenses became effectively shorter, and lens length is an essential asset for photography of small or distant birds.

So why go mirrorless?

My main motivation to go mirrorless was my subjects, the birds. Once you get used to bird behavior it becomes clearer how they respond to shutter sounds (particularly fast repeat shutter). Even if they don’t hide or fly off, you can often see them stop, look for the source of the sound, and perform a threat analysis — you know that you’ve put them at least on the edge of flight and need to back off, both for their sakes and for your chance to get a photo of them in normal, casual behavior.

Keeping my current Sigma 150–600 lens, I made the trade-off of a maximum focal length of 1.6*600 = 960mm with the 32Mpx (megapixels) of the 90D for 600mm and the 45Mpx of the R5, with the further gotcha that the R5 can’t directly take EF-mount lenses like mine, requiring an EF/RF adapter. More parts in the optical path isn’t ideal, but it turns out to work pretty well, maintaining good focus behavior, and the adaptor doesn’t involve a loss of light. This got me a good camera/lens combo with a slightly upgraded processor and slight improvements to ISO range.

However, it turns out you can push this a bit further.

I mentioned previously that I bought a 1.4x teleconverter to try with the 90D and the 600, but didn’t use it much. I didn't really explain that this is because the teleconverter wrecks the 90D’s focus capabilities, forcing you to centre-point focus, and making it almost unusable without a steady target (and ideally a tripod). Birds are rarely steady targets and I’m not a fan of tripod shooting. However, it turns out that the R5’s full-sensor autofocus and improved processor shrugs off that limitation and, at the cost of a stop of light (partially compensated by better ISO/noise balance) makes a permanently-fixed teleconverter a practical option, bringing my lens back to 600*1.4 = 840mm in regular usage. In fact I’ve also bought a 2x teleconverter to push that to 1200mm, although that’s starting to push the performance capabilities of the camera (though it’s still usable for some cases of still & distant birds, such as you might use a scope for). The lens usually “just” carries the 1.4x.

It has to be admitted though that a lens mount convertor *and* a teleconverter between camera body and lens isn’t an ideal situation, though the combination handles them quite well. A 45Mpx sensor allows you to crop far harder in post-processing and still retain a high resolution image. The eye tracking focus works on birds and animals well enough (despite occasional hunting) to be a viable third mode (besides single-shot spot focus for stationary birds and center-focus tracking for flying ones), at least enough to earn its place on the third preset that this camera adds above the two the 90D do. Tracking focus (AF-Servo) is also improved somewhat such that it has some hope of following a moving distant bird against a terrestrial background (rather than a conveniently empty sky). Note that if you do use eye tracking, there’s an extra menu option for human or animal modes; ensure you select the latter for wildlife.

However, long-end sharpness and noise seem a little worse than with just the 90D/600mm, leaving me open to alternatives.

One I’ve recently purchased (following a recommendation from Patrick Zephyr) is the Canon 800mm f/11 prime. Usually the distinguishing features of primese is that they a) have wide apertures and b) cost a fortune, so an f/11 prime at $999 is an odd beast. It should be too narrow to be useful for wildlife (low aperture requires slower shutter speeds, leading to motion blur) but it has an excellent optical stabilizer (claiming 4 stops!) which impressively offsets that problem. This leads to a lens which, in combination with the R5, can get very sharp focus (it’s particularly good at animal eye-tracking) in most conditions, though it performs less well in poor light. The lens is so light, and the stabilization so capable, that you can hold it still for longer, and use it for some of the spotting you’d usually delegate to binoculars. It’s not completely without its downsides — a long prime like this can make it hard to locate targets at a distance as you can’t “zoom out” to get your bearings, and the minimum focal length can be an issue if you want to do a “macro” shot of a small target (insects etc).

I’ve also got my eye on the Canon 100/500mm, which has also been recommended to me, but Canon’s refusal to allow third-party RF-system lenses has made me reluctant to sink further cash into the Canon ecosystem. If I hadn’t been able to start with the excellent and relatively reasonably-priced Sigma 150–600mm f/5–6.3 (the lens for wildlife hobbyists), I’d likely never have gotten into this hobby in the first place. I’m not looking forward to being stuck with a limited set of over-priced lenses in the long term.

Alternative kit

It’s worth noting that Canon have brought out two crop-sensor mirrorless cameras since I bought my R5 — the R7 and R10, which would probably both make excellent wildlife cameras, in prices and body sizes sitting between the T8i mentioned in the first article in this series, and the 90D, both significantly lower cost than the R5.

Other changes to kit and technique

One other piece of kit that I’ve added to the camera (and that’s moved with me from the 90D to the R5) is a GPS logger which sits in the flash shoe. This really simplifies proper tracking of images as it records the precise location of each photo in its Exif data and means you don’t have to manually (and approximately) add a location from memory when processing photos. It’s a big plus for logging to iNaturalist in particular. The only downside (apart from constantly having stock of AA batteries)? You can’t wear any sort of brimmed hat, which is definitely a preferred option in hot weather, as the two will collide every time you put your eye to the viewfinder.

I’ve also taken to carrying binoculars more while birding, having found a way to hang them from my sling bag that doesn’t constantly tangle with the camera strap (instead they can slide on the sling and hang from waist level when not needed). Sometimes you need the extra light, wider view, or lighter weight of binoculars, or you just want to enjoy watching a bird you’ve already adequately photographed.

For those keeping track then, my current main birding kit is:

Body / fixed kit:

Sigma lens set:

OR Canon lens:




Technique changes have been fairly minimal. Occasionally I’ll think more about setting exposure compensation more thoughtfully, or taking advantage of the R5’s infinite choice of focus points, but it’s still generally a process of mode-point-steady-shoot. One thing I do do though is to take shorter batches of shots and let the camera refocus between them so that a single bad focussing attempt doesn’t curse every shot you take of an individual, and I’ll often swap between a couple of focussing modes (particularly eye/manual) to hopefully get the best available shot.

A note on perspective

I recently heard about Theodore Roosevelt’s quote that “Comparison is the thief of joy.” This is probably as important for amateur photographers to remember as the rule of thirds, or how focal modes work. There are some astounding photographers out there, many professional, and it’s always the best shots, and the longest/rarest birding lists, that get shared. This can lead to the feeling that others are getting better shots and more species than you. Sometimes this is true; it might be because viewing and listing takes much less time than trying for the perfect shot, sometimes others are birding at times and places that aren’t available to you, and sometimes they do just have sharper eyes or have been doing it 5 times longer. But the joy of beginning is that each trip, each shot is a new chance, and the shorter your life list the higher the chance of something new.

Note on links

None of the links to kit are affiliate links; most links are to B&H because they always give plenty of info on their listings pages, and have good service, so I tend to shop there.



Richard George

Multilingual development and DevOps, with occasional politics and craft beer. Like the work? Contribute at