Dslr vs mirrorless cameras, which one to choose ?

The debate on “DSLR vs mirrorless cameras” clearly doesn’t date from today and things have since evolved. The first DSLRs arrived at the end of the 1990s with the production of the Nikon DA (1999), the Canon 1Ds (2002) or the Canon 300D (2003), the first DSLR camera designed for the public with a 6.2-million-pixel sensor! In short, DSLRs are not new. Besides, you want to know which DSLR to choose according to your needs, right?

Mirrorless cameras arrive much later, with the release of the Panasonic G1 and GH1 in 2008. The other brands will follow soon after, or almost, with Sony releasing the first mirrorless cameras with an APS-C format in 2010. In 2013, Sony revolutionized the world of mirrorless cameras with the arrival of their first full-frame mirrorless camera (24 x36mm). The two leaders of the DSLR world, Canon and Nikon, will follow the lead only six years later with the release of their first full-frame mirrorless cameras.

When mirrorless cameras first came out, about 10 years ago, I would have summarized the “DSLR or mirrorless camera” debate in the following way: if you were looking for a quality digital camera, you should have turned to DSLRs. If you wanted to shoot with a more compact and lighter camera, then you could choose a mirrorless camera. Today, and since a few years now, the debate is much more complex and with the arrival of full-frame mirrorless cameras, especially the Sony, the gap between the two types of cameras is getting tighter and tighter.

So much so that in 2019, if we only look at sales of bodies with interchangeable lenses (therefore excluding compact cameras / advanced compact cameras and bridges), the number of sales of mirrorless cameras has slightly increased above that of DSLRs. It is still very representative and finally, the interest today of asking yourself whether to buy a mirrorless camera or a DSLR, for example to start out in photography, makes sense. Come on, let me tell you everything!

In fact, we recently published a full article detailing all the best cameras we recommend for this year! We mention mirrorless, bridges, but also compact experts!

Before getting into a big debate, let me describe in a simple way the main difference between a DSLR and a mirrorless camera. It is simply inside the two bodies. In fact, I wrote a complete article on the best mirrorless cameras (for you!).

DSLRs (Digital Single-Lens Reflex) are composed of several mechanical elements, the main one being the mirror. To keep it simple and not go into any technical details, when you look inside your viewfinder, the light passes through your lens placed on the body to reach a mirror that will reflect the light to a pentaprism, up to the optical viewfinder where you can see the image. When you shoot, the mirror will tilt and the light will hit the sensor directly to record the image. For DSLRs, what you see in the viewfinder of your body is quite simply the reality. By the way, if you want to go further about DSLRs, I just wrote a complete article listing all the current Canon APS-C ones! You’ll find everything you need to know about these cameras and how I can advise you on your choice!

Mirrorless cameras simply have no mirror and the light passing through the lens lands directly on a sensor. A majority of mirrorless cameras (not all!) now have an electronic viewfinder (EVF). It is the sensor that will offer a re-transcription of the image to the EVF. In other words, what you see in the viewfinder of a mirrorless camera is simply a screen that transcribes reality. Below are examples of mirrorless cameras, the XT-4 from Fujifilm and the 6D Mark II from Canon (DSLR).

We get to the heart of the matter, the one that is the most important in my opinion. If you are wondering whether a DSLR and a mirrorless camera can produce the same image quality, I would say yes if you compare to equal sensor size. It’s always the same, you have to compare what can be compared in reality. I won’t repeat everything I wrote in the article about the different camera sensor sizes, but I’ll give you a short summary.

I often see in forums people comparing several bodies, DSLR or mirrorless cameras, but with different sensor sizes. However, this element is essential to take into account. Indeed, the size of the sensor influences in particular: the field of view (the famous crop factor), the increase in ISO, the depth of field (related to the aperture), the sharpness or the dynamics. All these elements generally affect the final image quality.

Simply put, for DSLR bodies, you have two sensor sizes: full frame sensor (24 x 36mm) and APS-C (15.7 x 23.7mm), although Canon APS-C sensors are slightly smaller. For mirrorless cameras, you generally have three common sensor sizes: full frame sensor, APS-C (as on a DSLR) and finally the Micro 4/3 (13×17.3mm).

So, make sure, if you’re hesitating between a DSLR and a mirrorless camera, to compare the same sensor formats. We will therefore talk about “full frame equivalence”, for the focal length, ISO and depth of field (so the aperture). Indeed:

• The focal length always remains the same but the field of view obtained varies according to the size of the sensor. You cannot compare the result of a 300mm on a full frame and on a Micro 4/3 sensor (equivalent to a 600mm),
• On the ISO side, they are reputed to be better on a large sensor (full frame). For example, the result at ISO 6400 on full frame is approximately equal to an ISO 3200 on APS-C or ISO 1600 on Micro 4/3,
• In terms of depth of field, I will not go into details of why and how (everything is explained in the article above), but it will obviously be necessary to find the same equivalence. Thus, a 25mm f/1.4 on an mtf sensor is almost the same as a 50mm f/2.8 on a full frame sensor. We will therefore not be able to compare “a large aperture” or “a maximum aperture” on different sensor sizes. Same goes for the quality of the bokeh in the background.

It won’t change the course of things that you know this, but let’s say that you now know that you have to compare what can be compared. I’m not saying that full frame is better all the time.

This is a point that everyone agrees on, relatively well anyway. In the majority of cases, a mirrorless camera will always be slightly smaller and lighter than a DSLR. Once again, we must compare what can be compared, that is, for the same sensor size. For entry-level mirrorless cameras, the difference exists. However, we are seeing more and more full-frame mirrorless cameras, and the difference between the latter and a full-frame DSLR is not huge. Just compare for example a Nikon D750 and a Sony A7III (both 24MP), the difference in weight is only 100g and the mirrorless camera will be only 1.5cm shorter. It’s not huge.

In fact, the difference in weight and size is especially noticeable between the pro DSLR models. It must be said that there are only few entry-level DSLR cameras with a simple design.

Regarding lenses, if we don’t take into account the full frame aperture equivalence (which is debatable), a mirrorless camera lens will always be lighter than a DSLR lens. As an example, here are three trans-standard lenses (with a focal length equivalent to 24-70mm – including the same field of view in the lens), opening at f/2.8:

• On MTF sensor: the 12-35mm (Panasonic) weighs 300g
• On APS-C sensor: the 16-55mm (Fujifilm) weighs 650g
• On full frame sensor: the 24-70mm (Canon) weighs 900g.

Clearly, the lens for mirrorless camera MFT is a winner in terms of weight, even if the output on the final photo will not be identical to the full-frame sensor with equal aperture. To really compare things that should be, and to get the same image from the same place, we can consider this for example.

As we can see, if we compare for the same final result, full-frame lenses are not necessarily bigger and heavier than a lens for a sensor half as small, like the Micro 4/3. Then again, in reality, it only matters if you shoot with a full frame sensor and often with very large apertures. The fact is that there are few FF lenses that have “small” apertures. The same goes for bodies where there aren’t really any entry-level cameras designed to be really light and compact, except for a few rare pancake zoom kits.

To simplify, the autofocus of a body works with two main technologies: phase detection and/or contrast detection. A few years ago, DSLRs still had a clear advantage over mirrorless cameras, which only used contrast detection, which is not really the case today. Many even use a combination of the two.

Concerning the AF points, the advantage now goes more and more to mirrorless cameras, which offer for a large majority of them a set of AF points on the whole image. The entry-level DSLRs (even in full frame like my 6D, which is certainly old now), offer only few AF points closely placed on the image in the viewfinder, which does not facilitate the composition when shooting, especially on a moving subject. Of course, there are still DSLR bodies that have an excellent autofocus like the Nikon D5 or the Canon 1D Mark II, but in the end, they are only affordable for a few people.

However, not all mirrorless cameras use the combination of the 2 systems (Panasonic for example uses only contrast detection) and the AF of DSLRs remains globally more efficient, especially in low light and in action.

I already mentioned it in the introduction the main difference between a DSLR and a mirrorless camera. This is a major point that in my opinion is of benefit for mirrorless cameras.

DSLRs have a so-called optical viewfinder. The main advantage is that you can directly visualize reality, your image, without any digital element. The optical viewfinder is moreover independent of the screen and saves a lot of battery power (see below). The live view mode (with the mirror up) on DSLR (for videographers) is not excellent either and is still slow. Another point is that you don’t see the exposure of your image in the optical viewfinder of your DSLR as you can on a screen that displays the scene by applying the processing settings in the process.

On the other hand, some mirrorless camera bodies (but not all of them, beware) have an EVF, an electronic viewfinder, connected to the screen. The real advantage of electronics here is that you can view the exposure of your photo directly in the viewfinder, and adjust the ISO, shutter speed or aperture settings from the viewfinder. You can also activate directly in the viewfinder the burnt areas of your image. You can see the impact on your photo live. Once the photo is taken, you can also view it directly in your viewfinder, zoom in on it, and so on. Finally, you have the Focus peaking option which allows you to view sharp areas in manual focus directly in the viewfinder.

However, the electronic viewfinder does not only have advantages in my opinion. First of all, not all mirrorless cameras have EVF. So, you have to compare what’s comparable because all DSLRs have an optical viewfinder. However, the EVFs in some mirrorless cameras still have trouble holding up when the subject is moving or when the brightness becomes very low, resulting in the final image sometimes being jerky or blurred. Finally, optical view finding is still faster because the mirrorless camera body has to convert the scene into a digital image for it to be visible while on a DSLR, you see it live, although the latency time on the latest mirrorless cameras has been reduced considerably.

Last point to note in my opinion: the depth of field, at least the tester. On a DSLR, it’s not easy to use because it’s too dark, too difficult to read. With an EVF, you can vary your depth of field without affecting the brightness of your viewfinder (and you can see the result directly in the viewfinder). It is also worth noting the advantage over EVFs of being able to display “image renderings” in your viewfinder, for example to view B&W directly.

JI won’t spend six months here. If you’re looking for cameras in 2020 with the largest lens selection, there’s not even a debate to have, you’re going to choose a Canon or Nikon DSLR which both offer a huge selection of lenses and a wide choice of both native and third-party brands.

The gap is gradually closing, but the difference between the possible choices of mirrorless camera lenses compared to DSLR lenses in 2020 is still quite important. In the mirrorless camera family, Sony (FE) and Fuji will offer the most choices. However, there is an added advantage for mirrorless cameras. The removal of the mirror has allowed to reduce the size of the body but also to design shorter mounts allowing the possibility to add adaptor rings to take advantage of other brands’ optics in other mounts, although there are often restrictions.

Also note that (even if the gap is catching up little by little) for specific fields such as sports or wildlife, the choice remains very limited for mirrorless cameras.

Finally, as for optics, the choice of camera accessories for DSLR bodies remains much greater than for the mirrorless cameras.

This is a point on which almost everyone agrees, the mirrorless cameras appear for many photographers more discreet. Indeed, since there are no mechanical parts, the bodies are very quiet. This is particularly appreciated for street photography, weddings, etc..

When it comes to size and weight, as mentioned earlier in the article, everything will depend on what you have. Full-frame mirrorless camera bodies equipped with telephoto lenses are almost as ” noticeable ” to me as my 6D + 70-300 L IS.

Things clearly change here between a DSLR and a mirrorless camera. On a DSLR camera, the fact of having a mirror limits the reading speed of the latter (and of the curtain in front of the sensor). On a mirrorless camera, the electronic shutter makes it possible to reach higher shutter speeds but also to increase the rate of the burst. The Sony A9, for example, offers 20 frames/second.

The advantage of not having a mirror is that it also limits the risk of breaking mechanical parts. You will smile, but I had a problem with the mirror of my 6D which had a problem (probably a manufacturing issue). Nevertheless, the mirror has the small advantage of protecting the sensor from dust when you remove the lens, although in practice even if sensors in mirrorless cameras are more likely to get some, they will only be seen in specific shots. In addition, you can always clean them with a pear or a stick provided for this.

Generally speaking, DSLRs do not offer body stabilization (except for Pentax) and prefer optical stabilization (basically you buy a stabilized lens or not!). This simply comes from the fact that with a DSLR, if the sensor is stabilized, it doesn’t allow you to enjoy it with the viewfinder. Indeed, you see what the lens sees and not the sensor. Conversely, on mirrorless cameras, whether you’re aiming at the screen or in the viewfinder, it is always what the sensor sees that is displayed.

In mirrorless cameras, sensor stabilization is more and more common, especially in 5 axes (for example at Sony, Olympus and Panasonic). Olympus has for example built stabilized bodies from the beginning. Nikon has chosen from the start to stabilize its sensors with the Z6/Z7 (but not the recent Z5) in order to do without them on the lenses to reduce their weight/cost. Note that it is possible on some Micro 4/3 mirrorless camera bodies (Olympus and Panasonic) to combine body and lens stabilization, called Dual IS, just like in full-frame mirrorless cameras at Canon now with the R5/R6.

Example of a camera with a built-in 5-axis image stabilization, the Sony A7 III
Check the price of this mirrorless camera on Amazon

There are two points that I think need to be addressed. The first and most important is battery life. Clearly, there’s no debate here, DSLRs, whatever they are, have a great advantage over any mirrorless camera. Mirrorless cameras, because of their electronic components continuously activated (especially the viewfinder) consume much more battery power. In addition, because these cameras are basically designed to reduce the size of the camera, the batteries themselves are also more compact and therefore offer less capacity. It all depends on the model, but it’s common to hear 300-500 shots per battery with Sony cameras, whereas a current entry-level DSLR displays 500/1000 shots, or even more than 1500 shots. Pro DSLRs can even exceed 3000 shots with their huge battery. So it’s quite a difference and a point to know for those who need a lot of autonomy (long exposure, working in the cold, hiking over several days, etc.). However, manufacturers are making more and more efforts and we are approaching 1000 views per battery on some recent mirrorless cameras, no doubt that this will continue to improve in the future.

Another important point to note, I would say that overall DSLRs are more resistant tanks. For example, Sony mirrorless cameras, even high-end ones, are not tropicalized. Clearly, it’s not easy to combine the robustness of DSLRs with the weight and size constraints of hybrids, but in the end, most mirrorless cameras are robust enough for the majority of uses.

Choosing a camera is not that simple and you should not necessarily believe that getting a mirrorless camera body will cost you less than a DSLR. You just have to compare again what can be. In my opinion, there is not much price difference between entry-level mirrorless cameras and DSLRs. You can find the first kits from around 400/500€. Even on high-end bodies, the difference is not huge for example if you compare the price of a Canon 1D X or a Nikon D6 compared to a Sony A9II or a Nikon Z7. For equal performance (including sensor size) and similar range, we roughly stay in the same price range. The debate is therefore not between “mirrorless cameras or DSLRs” but rather a comparison between sensor sizes.

Regarding lenses, the real difference is more between high-end and low-end than between DSLR and mirrorless cameras. For example, a 25mm f/1.8 from Olympus is more expensive than a 50mm f/1.8 from Nikon/Canon/Sony in FF, …

On the other hand, for the same sensor size, if you buy lenses for full frame sensor, mirrorless cameras are clearly not cheaper (rather the opposite given their “youth”). A Canon RF 70-200mm f/2.8 costs about 2700€ compared to 2000€ for a Canon 70-200mm f/2.8 L IS III USM. Note also that in the world of DSLRs, it is easy to find second hand old lenses that are still very good. On the other hand, on the mirrorless camera bodies, the ranges being recent, you will really have a hard time finding second hand lenses.

This is still a big advantage for mirrorless cameras, at least for the brands that have decided to be able to “upgrade” their equipment with body updates, a bit like updating your phone. I’m thinking in particular of Fuji, which currently offers body firmware upgrades providing better performance, such as an increase in the number of AF points, better tracking in AF-C mode, or improved optical image stabilization. Sony also does it in reality, as do Nikon and Canon who have followed suit. Besides, between us, it was simply impossible to add software functions to an optical viewfinder on a DSLR body!

Sony for example, instead of multiplying the ranges, decided to release a new body, but the old one remains in the catalog, to be used as a lower range. In fact, it’s the same with a lot of brands. Nikon in its turn proposes to update the firmware on the Nikon Z. This is a plus for me if we compare to DSLRs whose updates are often only used to fix bugs and ensure compatibility with new products”.

Last point of this long article, the video mode. Clearly, I am no specialist and bought my 6D to do 100% of photography. But a lot of people practice both. Mirrorless cameras are undoubtedly better, more advanced. DSLRs have always been a hassle when filming, partly because manufacturers believed that a DSLR was used for optical viewfinder shooting. Whereas on a DSLR, the video is only done in live view (roughly equivalent to a mirrorless camera with the mirror up). Today, with small compact cameras, easy handling, a swivel and/or touch screen, mirrorless cameras bodies are great for capturing beautiful moments on video.

To conclude, everyone more or less agrees that mirrorless cameras are the future in photography. But, I repeat, if you are wondering, try to compare bodies that are comparable. Don’t compare an Olympus Micro 4/3 with a Canon 6D Mark II, it would make almost no sense.

Clearly, there are more and more advantages to mirrorless cameras, but don’t be fooled by saying that they are cheaper, lighter and smaller. It’s all a matter of comparison in reality. High-end bodies + mirrorless camera lenses are very expensive and are just as big as those in DSLRs.

To conclude on the famous debate of “DSLRs or mirrorless cameras“, I would say that it all depends on your desires and, of course, your budget. For those who don’t want to do video at all, who want a wide choice of lenses (new and second-hand especially), I would still advise you to go for a DSLR. This is also the case for many photographers who are already very well equipped with DSLRs and who don’t want to have to buy everything! For others, choosing a mirrorless camera kit will never be a bad decision. The goal is to buy the right equipment that suits you, to get you started and to familiarize yourself with it. Once you’ve progressed, you’ll feel the need to change your range! In any case, a lot of mirrorless cameras are what I consider to be good value for money, often being less bulky (for the Micro 4/3 for example).

For those who are interested in choosing your next camera, I invite you to read my article on advanced compact cameras. This is a type of camera that might be just right for a lot of you, knowing that some of these bodies are better than some DSLRs and entry-level mirrorless cameras!

See you soon,

Sylvain