DSLR or Mirrorless: What’s the Difference?

If you are looking to buy a new camera system, it’s highly likely that you may have looked at a CSC system (Compact System Cameras are often referred to as mirrorless cameras). Mirrorless cameras are definitely the new kids on the block but, as technology advances, they are starting to become very popular with both consumer and professional photographers and are now starting to encroach on the traditional DSLR market. The question is do they live up to all of the hype? Can a mirrorless system really compete with a DSLR?

I have been using a mirrorless camera alongside my Canon DSLR for over 4 years, with a brief spell of shooting exclusively on a CSC camera. The reality is that both the new CSC and the traditional DSLR have their own pros and cons. The real question is what is the best fit for you and the way that you take your photos.

mirrorless or dslr camera
Captured on a family walk in the Yorkshire Dales, the compact Olympus EPL2 with standard kit lens has done a great job of capturing an image which I simply wouldn’t have taken if I did not own a mirrorless system, because I would have never taken the full DSLR gear with me whilst carrying a 2 year old boy in a backpack!

The Viewfinder

As the name suggests, mirrorless cameras lack the mirror reflex optical viewfinder that means that the lens can sit nearer to the image sensor. The advantage of this is that both the camera body and the camera lens can be far more compact than what we find in a traditional DSLR. The disadvantage is the lack of an optical viewfinder dictates the need for an electronic means to compose your images, either via an electronic viewfinder (EVF) or simply by the screen on the back of the camera.

So, now we have the first point to consider when choosing between the two systems. First of all I would never suggest that you buy a camera that does not have a viewfinder of some sort (either optical or electronic). Whilst using the rear screen can be useful in some instances, in general it is far easier to compose via a viewfinder and you will find that your posture is far more stable, resulting in less camera shake, as opposed to holding a camera whilst trying to compose on the screen.

viewfinder on mirrorless cameras
In my opinion, the Fujifilm cameras (and other mirrorless systems) excel at long exposures. For this shot I fitted a 10x ND filter and I was still able to compose and auto focus the shot by using the EVF. So much simplier than the compose, focus and fit filter method often needed with a traditional DSLR.

As for the actual viewfinder, they both have their advantages. An EVF allows you to almost see your final image before you actually take it. For example, you can gauge if the shot is under or over exposed (especially if you choose to have a live histogram showing whilst shooting) as well as being able to preview any picture styles you may have set (such as monochrome). However, you are essentially looking at a small display screen and over periods of extended use it may lead to eye strain (depending on your eyes of course). Another point to consider (although not such an issue with later cameras) is that if you are shooting in poor light, you may find that you have a time lag in the actual display, but at least you will be able to still see your subject (which isn’t always possible with an optical viewfinder). In contrast, the optical viewfinder does not require any electronic parts and as such will always pretty much let you see what is before you – although you will probably see more through an EVF if the light is particularly dim! Also, the optical viewfinder does not require any power to operate.

mirrorless cameras
Some of the faster mirrorless lenses (such as the Olympus 45mm 1:1.8) can really deliver some great out of focus backgrounds with careful composition.

Battery Life

Battery life is also a major consideration when choosing a system. Mirrorless cameras by design are generally a lot smaller than a DSLR, meaning there is less room for a battery. So, their batteries are also smaller which means that they hold less charge. However, mirrorless cameras actually require far more power than a DSLR due to the fact that the screen is effectively always on (either in the viewfinder or the rear of the screen). So a camera that uses more power yet has a smaller battery can mean only one thing: poor battery life. As an example, if I am out shooting with my Canon 5DS, I can quite easily get through a day using only one battery. However, if I am shooting with my Fujifilm X-T1, I will probably use at least three batteries. OK, the batteries are small enough but it is still a pain to keep having to swap batteries. This also means more time spent charging batteries after a day’s shooting.

Auto Focus System

Generally in use, the main obvious difference (apart from the EVF) is the auto-focus system. Previously, I have found the AF system of a DSLR to be far more responsive, although I do tend to find the AF system of a mirrorless system to be more accurate. The reality is that if you shoot landscapes (or anything that generally is not moving) then you will find the AF of any mirrorless system is more than adequate. However, nature photographers may find the AF system of a mirrorless can be a bit hesitant. At this point I must stress that the AF systems of the latest mirrorless systems are greatly improving and it probably wont be long before new cameras such as the Fujifilm X-Pro2 can match the performance of the traditional DSLR.

mirrorless or dslr wildlife
Whilst the AF of some mirrorless systems can leave something to be desired, I generally always found the Olympus AF system to be quite adequate.

Manual Focus

An interesting thing to know though is that if you prefer manual focusing (or indeed enjoy using old lenses which only offer manual focusing) then a mirrorless system is probably a far better fit for you. The reason behind this is that the majority of mirrorless systems offer a way to assist your manual focusing such as focus peaking and also offer a way to zoom into your image (whilst composing) so that you can accurately see if you have nailed the focus. Believe me that once you have manual focused on a mirrorless system, you will find focusing on a DSLR a slow and inaccurate affair.

focus peaking mirrorless
It would have been virtually impossible to compose this shot through a DSLR viewfinder – it really was as dark as it looks! However the EVF and focus peaking made composition and manual focusing a breeze.

In Conclusion

So as you can see from the points above, the choice between using a mirrorless and DSLR really depends on what you photograph and the way that you like to work. You will be pleased to hear though that the one thing you do not need to consider is image quality. The majority of mirrorless systems on the market, when coupled with good glass, can produce images that can equal, or in some cases exceed, virtually any modern DSLR. Image quality really is a non-issue but do please keep in mind that you will have to budget for good glass to achieve these results, and more often than not these lenses can be expensive compared to a DSLR counterpart.

olympus mirrorless camera wildlife landscape
The Olympus cameras have a great ‘live bulb’ feature where you can view long exposure images being recorded whilst you take an exposure, which means than you can accurately gauge when to stop your exposure. This shot was taken with a pinhole lens on an Olympus OM-D.

Whichever system you use, you can be assured that they will be able to produce results that we could have only dreamed of 10 years ago. Personally I use both, choosing to use a compact Fujifilm X100T (fixed 35mm – FF equivalent – lens) with a couple of of lens convertors (28mm & 50mm) alongside my Canon 5DS and numerous lenses. The Canon is my workhorse and produces the results that I need whilst my little X100T is the camera that I use for my personal work. The Fuji is always with me and produces shots that I would have missed with the Canon. The Fuji is also a pleasure to use and lets me simply enjoy taking photographs, which surely cannot be a bad thing!

Further Reading: “Canon EOS 5DS – a Landscape Photographer’s Dream?


Visit Jason's website

Based in Newcastle-Upon-Tyne, UK, Jason Friend is a professional travel and landscape photographer. For Jason, photography is more than a job: it is an opportunity to inspire. National Geographic, British Airways and Rough Guides represent some of the many high-profile clients Jason has inspired and worked with along his journey. Recently, Jason founded ‘The Legacy Project’, a fascinating not-for-profit endeavor to capture the mystifying stone remains of prehistoric sites scattered across the British Isles.

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