Mirrorless vs DSLR cameras: the 10 key differences you need to know

Mirrorless vs DSLR: introduction

The great mirrorless vs DSLR camera debate has been rumbling for a few years now. So are we any closer to establishing a winner? While the decision will always be a personal choice, the camera manufacturers are starting to make it a lot more straightforward. 

Both Canon and Nikon have been discontinuing, or simply not updating, their DSLR models in recent years. This means mirrorless is very much the default format for new cameras and is our recommendation for most people. But it isn’t quite that simple, because DSLRs continue to offer excellent value and have large, established ranges of lenses. And that counts for a lot during these financially-challenging times.

Back in the early days of mirrorless cameras during the late 2000s, the situation was very different. If you were a pro, you tended to pick up a DSLR. Hobbyists and amateurs, who were more bothered by weight and portability, would instead lean towards their mirrorless counterparts.

This has now changed. With flagship cameras like Sony A1, Nikon Z9 and Canon EOS R3, the giants have confirmed that mirrorless is both the present and the future for their best professional cameras. Incredibly, the Nikon Z9 doesn’t even have a mechanical shutter, which makes it the real flag-bearer of a new, all-electronic shooting style.

But what exactly are the differences between a mirrorless cameras and a DSLR? And are there any situations where you should still consider the latter? Our in-depth guide is here to give you all the answers – including a simple explanation to that first question.

Mirrorless vs DSLR cameras: what’s the main difference?

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Let’s start with the basics and look at the key differences between these two types of cameras. The key is in the names. DSLR stands for Digital Single Lens Reflex, which works by the light hitting a mirror angled at 45 degrees. That light goes straight up into an optical viewfinder which allows you to see precisely what the lens is looking at. This is a true optical path, with no digital processing in the middle. 

When you’re ready to take a photograph, that mirror moves out of the way – to reveal the image sensor – and if you’ve used one in the past, you’ll be familiar with the satisfying (but fairly loud) noise it makes as it does so. 

By contrast, mirrorless cameras – you’ve guessed it – don’t have a mirror. With these cameras, the light passes through the lens and straight onto the sensor to be processed. It’s then displayed either on the monitor on the back of the camera, or in the electronic viewfinder (EVF), which is in essence a very small monitor. This time, when you take a picture, the camera is simply recording what is on the sensor at that moment in time. 

DSLRs use the same technology as their film counterparts, which have been around for decades. They’re very familiar for anybody who has been serious about photography in recent years. Legacy companies such as Canon, Nikon and Pentax have been making them for all those years and so have a lot of experience to draw from. 

Editor’s notes

(Image credit: Nikon)

We’ve now officially heard from Nikon that it’s ceased production on two of its most popular entry-level DSLRs, the Nikon D3500 and D5600. And while Canon hasn’t yet made any similar statements about its DSLRs, it hasn’t released a new one since the Canon EOS 90D in 2019. The only company that appears to be single-handedly carrying the torch for new DSLRs is Pentax, which launched the K-3 III in 2021. But in short, don’t expect to see any new DSLRs launched from now on. Mirrorless is the future, but second-hand DSLRs continue to offer great value. 

These days, almost no new DSLRs are introduced to the market, but there’s still plenty you can buy. They tend to have great handling, offer fantastic image quality and one advantage that doesn’t look set to go away for a while yet – extremely impressive battery life. 

By taking away the mirror, mirrorless cameras give you several advantages (and very few disadvantages). The key one is that, since they don’t need that big clunky mirror setup, they can be smaller and lighter than their equivalent DSLR counterparts. 

Some of the tasks of the camera, like autofocusing, can take place on the sensor itself, leading to super-quick focusing speeds. Speaking of speed – with no mirror to move out of the way, frame rates aren’t limited so much by physicality. Mirrorless cameras routinely offer at least 10fps, with some high-end models delivering 20fps or 30fps at full resolution, with continuous autofocus between each shot. 

In the beginning, mirrorless cameras tended to use smaller sensors than DSLRs. But now, the most popular sensor size in these models is full-frame, with Sony, Nikon, Canon and Panasonic all producing this type of camera. APS-C is also a common sensor size, for both mirrorless and DSLR. All of this means that there’s no generally discernible difference between outright image quality in DSLRs and mirrorless cameras, no matter which you choose to go with.

The electronic viewfinders found on early mirrorless cameras weren’t particularly great, being low in resolution and slow. But over the years the technology has advanced so much that many photographers now prefer the super high-resolution viewfinders on the current crop of high-end mirrorless cameras. They show a truer reflection of what your final image will look like, as well as allowing you to see a preview of your image after you’ve shot it.

All of this makes it sound like mirrorless is the obvious winner – and while the fact that no new DSLRs have been announced in the past 12 months might seem to back that up, there are still some advantages of the older technology. 

We’ll discuss the main differences in the coming pages to help you come to a firm conclusion, so use the arrows at the top of this page navigate your way through them.

By taking away the mirror, mirrorless cameras give you several advantages (and very few disadvantages).