The Time Has Come: A Case for Mirrorless Cameras

As we begin 2021, it has been a full 13 years since the release of the Panasonic Lumix DMC-G1, almost eight years since the full-frame Sony Alpha a7 was introduced, and more than two years since Canon and Nikon announced their full-frame mirrorless cameras. In other words, there has been plenty of time to read the writing on the wall (as well as the sales figures), which clearly states that mirrorless interchangeable-lens cameras are becoming more popular every year and are the developmental focus of most camera companies, compared to their DSLR stablemates. If one needs further convincing of this trajectory, the Sony Alpha 1 just became the first mirrorless camera labeled as a brand’s “flagship.”

Before some of you get upset with me for noting that camera technologies evolve, allow me to mention that while I own and use a mirrorless camera, I still shoot primarily with DSLRs, and there are reasons a DSLR makes sense for some photographers. However, I am not the future of the camera market nor am I overly concerned with using the latest/greatest cameras; I equally appreciate the current counter-trend—film’s re-emergence and the embrace of 35mm photography.

If a DSLR, rangefinder, or point-and-shoot work for your needs, that is fine, but the general criticisms waged against mirrorless (sensor size, form factor, autofocus, viewfinder, insufficient lenses) are no longer applicable, and there really is no going back—Canon, Sony, and Nikon have all made that clear in recent years; FUJIFILM, Panasonic, and Olympus are all-in; Leica makes mirrorless; and then there’s Pentax, who, 10 years ago, released mirrorless offerings, but is now sticking to its DSLR roots. So, let’s be real—whether you are starting from scratch to build a system, or an enthusiast looking for the strongest technological package, or a pro seeking state-of-the-art gear, mirrorless cameras should be a part of your kit.

As mentioned, there are still reasons to buy a DSLR, and I reject the rhetoric of one “vs.” the other. Mirrorless and DSLR (and point-and-shoots, medium format, and smartphones) will comingle in the camera bags of many shooters for years to come, and you will be a truly evolved photographer when you realize that each type of camera has its advantages. But with the continued strides made in mirrorless camera technology, it’s important to understand the advantages these systems offer.

It’s Called Mirrorless for a Reason

Eliminating the mirror mechanism of the DSLR is at the heart of the mirrorless concept. An internal mirror to reflect light into the viewfinder and then flip out of the way when the sensor is to be exposed necessitates space, time, and movement; a mirrorless camera can therefore be smaller, faster, and quieter by design. With no mirror and pentaprism or pentamirror housing, the potential reduction in size is fairly obvious, but without a mirror moving up and down, a camera can be quieter and will also produce less vibration, which can blur the image. These are crucial advantages for so many photographic pursuits. Also, the mirror mechanism is just that—a mechanism with moving parts that will eventually flaw or even break, possibly limiting the life of your camera and/or requiring maintenance.

Autofocus

While autofocus had been a point of concern for early mirrorless cameras, those days are pretty much gone. DSLR cameras were able to utilize phase-detect autofocus better because, in addition to their imaging sensor, they contained separate sensors to detect focus, while mirrorless cameras relied on a contrast-detect AF system as part of their one imaging sensor. Contrast-detect AF can be more accurate but is generally slower, and that was an advantage for DSLRs, especially for larger sensor cameras preferred by sports, news, and wildlife photographers.

However, mirrorless technology made leaps in recent years to create a hybrid autofocus system, enabling fast phase-detect and contrast-detect autofocus on the same sensor that captures the image. Using one sensor eliminates the potential back-focus inaccuracies, which can be a by-product of the DSLR’s multiple-sensor design. Size and system economy are benefited, as is speed of focus, but improved focus accuracy is increasingly important as megapixel counts rise—higher-resolution cameras are less forgiving to even slight focus errors. The new Canon EOS R5 full-frame mirrorless is noted as having one of the top autofocus systems across all camera types.

Live View

Conceptually, the idea of looking at a digital screen to compose an image is the cornerstone to mirrorless camera use, and this is a convenience adopted from digital point-and-shoot and cellphone cameras. For many people, especially those recently entering photography, this practice is second nature and, in general, a comfort with large LCD screens being a built-in advantage. The latest mirrorless cameras have sharp, high pixel-count rear screens that can flip out or tilt for easier odd-angle compositions. Simply put, you no longer have to see through the viewfinder to compose. Of course, DSLRs have also embraced live view technology but often with slower contrast-detect systems built into their image sensors and/or with video applications in mind. The Panasonic Lumix DC-S1 Mirrorless Digital Camera has a 3.2" 2.1m dot triaxial tilting LCD with a “Live View Boost” viewing mode.

In-Body Image Stabilization

Mirrorless cameras have led the way in terms of in-body and 5-axis image stabilization. Some DSLRs now have in-body stabilization, but the mirror mechanism is problematic for “IBIS” and they tend to rely on lens-based stabilization, while mirrorless developers were creating in-body systems from the ground up. Mirrorless cameras offer some of the most effective in-body stabilization systems, for example, the FUJIFILM X-T4 Mirrorless Digital Camera. Having the stabilization system in the camera also enables shake reduction to be used with older lenses, even those built long before “image stabilization” existed.

Lenses

Mirrorless cameras quickly became a plaything for many photographers to experiment with by utilizing lenses not proprietary to their camera system. The use of vintage and third-party lenses of all varieties on mirrorless cameras has long been a draw, but one generally reserved for tinkerers and lens geeks. For years, it was the dearth of new high-quality lenses for mirrorless systems that dissuaded photographers from embracing these cameras. Again though, this is no longer an issue. It is true that DSLR mount systems, some of which go back decades, have a large catalog of compatible lenses, which mirrorless systems still do not match, especially when it comes to ultra-telephoto and specialty lenses, but either through their own R&D or in partnership with other manufacturers, camera companies have closed the gap by continuing to introduce more high-quality lenses for their mirrorless systems.

And mirrorless camera designs enable certain advantages for lens designers. The distance between the lens mount and image plane in a camera is called the flange focal distance. Without the room needed for a mirror, mirrorless cameras have a much shorter flange distance than a DSLR, thus allowing the adaptability of lenses designed for much older rangefinder cameras and cinema lenses. Also, with the proper adapter, mirrorless cameras can utilize new lenses from other manufacturers and third-party lenses designed specifically for a particular mirrorless system’s mount. The lens options for mirrorless are growing much faster than those for DSLRs. To this point, Canon announced last year that they do not plan to currently develop new EF lenses.

Large lens libraries are huge advantages of the older mounts, but technologically the mounts are ancient and can be limiting. Nikon made an effort with the Z Series to create a forward-thinking mount that was larger than their classic F line. This made it easier to develop high-quality glass and even led to the revival of the Noct with the release of the Z 58mm f/0.95 S. Nikon is far from alone in this regard.

Mirrorless systems also benefit from the ability to redesign certain focal length lenses to be smaller and lighter. Again, because of the flange focal distance, extreme wide-angle lenses, especially fast-aperture lenses, can be made smaller than their DSLR counterparts. Also, since DSLR cameras’ phase-detect autofocus can struggle to find focus when using lenses that are not particularly bright (those with a maximum aperture of f/5.6 or smaller), extreme telephoto lenses needed to be large to provide the fast apertures required for sports, wildlife, or other photo disciplines. This is not the case when using the hybrid AF sensor on mirrorless cameras, which gives lens manufacturers more freedom to create lighter, smaller, more affordable ultra-telephoto lenses. This is an area ripe for development, and Canon surprised many people in 2020 by introducing new 600mm f/11 and 800mm f/11 lenses for its mirrorless R system.

Form Factor

Smaller camera size has always been a rallying cry for mirrorless cameras. Initially, it seemed to be the only rallying cry, but that too has changed, and ironically not necessarily with the development of smaller and smaller mirrorless cameras. As mentioned, without a mirror and pentaprism housing, mirrorless cameras allow more compact form factors, and many, such as the Olympus Pen series cameras and Sony a6600, embrace this advantage, but as mirrorless cameras improved technically and incorporated full-frame sensors, their bodies grew in size. It also seems that photographers, particularly professional and advanced amateurs, appreciate the large grips and rounded, rugged features of the DSLR, and several mirrorless cameras now also sport an ergonomic size and shape, comparable to a standard DSLR. Overall, however, mirrorless cameras are trimmer and definitely lighter than DSLRs.

Electronic Viewfinder

Finally, the sticking point. The optical viewfinder is one feature that DSLR users still tout as “better” than what mirrorless cameras can offer, and it is true that many photographers, even those raised on smartphone cameras, recognize the advantage of really seeing your subject via mirrors and glass as opposed to through a miniature LCD screen. But, as is the theme of this article, the drawbacks of electronic viewfinders are shrinking just as we, as photographers, are becoming more accustomed to using them. Primarily the size, resolution, and brightness of EVFs have improved over the years, as have the processors, which reduce buffer time and image lag. The Sony Alpha a7S III offers a 9.44m-dot resolution EVF for incredibly bright and detailed image composition.

Electronic viewfinders also offer features that optical viewfinders can never duplicate, primarily the ability to see real-time changes in exposure as you adjust camera settings. It is a giant hurdle removed. Also, functions such as focus peaking and focus zoom make accurate focus, even in manual focus setting, easier to achieve. For those photographers wanting the best of both worlds, the FUJIFILM X-Pro3 Mirrorless Camera offers a hybrid system with both an optical and an electronic viewfinder option.

Silence

Although mentioned earlier in this article, I feel it important to note one benefit that mirrorless cameras truly enjoy over DSLRs, and that is the silence with which they can operate. While the electronic shutter function has limitations, the ability to shoot a mirrorless camera in complete silence (not damping sound) is a monumental advantage for the type of photography I normally do—street photography, cultural event photography, and on-set still photography. It is hard to imagine how different my workflow and success rate would have been if high-resolution mirrorless cameras were available when I started these aspects of my photographic work.

Let us know your thoughts on the evolution of mirrorless camera technology, and which feature brought you into the mirrorless camp, or what keeps you content with a DSLR. And to further this conversation, listen to this episode of the B&H Photography Podcast, in which two bird photographers discuss the pros and cons (mostly pros) of the latest mirrorless cameras.