Mirrorless cameras have been around for a while now. While they have taken up the lion’s share of the digital camera market, they haven’t completely killed off their DSLR siblings.
There are clear advantages to owning a mirrorless system. But they also come with disadvantages which need weighing up to understand if you can benefit with a mirrorless or DSLR system.
Main Differences Between a DSLR and Mirrorless Camera
Size and Weight
The first thing you would notice about the mirrorless camera is its smaller size and lighter body. This is down to the removal of the mirror, which is necessary for a DSLR to operate. For example, the Canon R5 mirrorless camera weighs 738g – 152g lighter than the Canon 5D Mark VI. Similarly, the R5s dimensions (138 x 98 x 88 mm) are much smaller than the 5D Mark VI (151 x 116 x 76 mm).
Other systems across different brands and versions are similar when compared to the DSLR siblings. The Nikon Z9 is over 300g heavier than the D850. In this case, the mirrorless is heavier than the DSLR. Here, Nikon added more features that needed a heavier mirrorless system.
Viewfinders & Battery Life
As the mirrorless camera came from removing the blocky mirror inside, there is nothing to bounce light from the scene to the viewfinder. The answer comes in the form of an Electric Viewfinder. This captures the scene from the lens, and sends it to the photographer composing the shot. For me, looking at the scene on a small TV screen felt a little strange, and took time getting used to.
As the viewfinder in mirrorless cameras is electric, it uses power from the battery pack. The issue here is you don’t get so many shots per battery compared to DSLR cameras. The 5D Mark VI captures approx. 900 shots per battery, whereas the R5 will get you around 320. The D850 will take an incredible 1100 more shots per battery compared to the Z9.
Frame Rates
Some photographers need to shoot a fast succession of images to ensure they capture the scene they need. Sports photographers can’t rely on one image, so a faster frame rate are needed. A frame rate is how fast a camera can shoot and process images in one second. The Canon R5 can capture up to 20fps (electronic shutter; 12 mechanical shutter), where the 5D Mark VI gives you 7 shots in the same time frame. You get a similar frame rate when comparing the Z9 and D850 from Nikon, with 30fps vs 7fps respectively.
It is important to know the difference between both shutter types to make a full judgement. The electronic shutter can make objects seem strange (car wheels looking oval) due to its rolling effect. Even with the use of the mechanical shutter on mirrorless systems, expect to get double the frame rate compared to DSLR counterparts. The benefit with cameras such as the R5 and Z9, there is less chance for camera shake due to a lack of mechanical movement inside.
Autofocus & Focal Points
Digital cameras use a focal point system that allows the photographer to select an element in the scene. The more focal points there are, the photographer can fine tune exactly where the focus falls strongest. The 5D Mark Vi has 61 focal points, whereas the R5 uses almost 100 times more (5940 focal points). Similarly, the Z9 has 340 more focal points than the D850.
The biggest benefit with mirrorless cameras is the AF tracking. By tracking Eyes (animal and human) and vehicles, it makes it easier to lock onto a moving element. This way, you don’t need to refocus and risk missing the shot. On top of this, they also use focus tracking and stacking in-camera, reducing the time needed for editing post-shoot.
Sensor
Both DSLR and Mirrorless camera systems use CMOS sensors - the difference is in the resolution. The R5 has a resolution size of 45 MP, where as the 5D Mark IV is comparatively smaller at 30 MP. *It is important to know that the R5 came 4 years later than the 5D. Saying that, there is a 4 year difference in the Z9 and D850, yet both have a 46 MP sensor.
The main differences that we do see is the sensor is no longer protected by the mirror. The solution to this problem is an anti-dust sensor mechanical system. For mirrorless systems, the sensor is where the image stabilization comes from. The benefit to this is that all lenses are equally affected, as apposed to each lens carrying their own.
Lenses
Photographers may choose lenses over a system as the glass is what provides the perspective. Prime lenses and large apertures are necessary for some fields. Other areas need a portrait, wide angle or telephoto lens. There are more lenses for DSLRs as they have been around longer and need to fit the wide range of subjects and fields. This is one area where mirrorless systems lose out, but there is a way around it with the use of a mount adapter.
Currently, there are 257 lenses for Canon 5D MIV's Canon EF mount. 77 of these come with Image Stabilization. There are 34 lenses for Canon R5's Canon RF, where the sensor stabilization is up to 8.0-stops. For Nikon D850's Nikon F mount, there are 316 lenses, 107 of which with Image Stabilization. There are 33 lenses for Nikon Z9's Nikon Z lens mount with sensor stabilization up to 6.0-stops.
Mirrorless Vs. DSLR Cameras
Having a smaller, light camera makes the mirrorless camera a better system for travel and landscape photography. It benefits any field or subject where handheld shooting is a necessity. But, there is a tradeoff. Electronic viewfinders mean less shots per battery. Forcing you to buy, charge and carry more for the same, comparative battery life. Not only is it an extra expense but adds extra weight.
The sensors on comparative systems (high end DSLR vs. high end mirrorless) have similar sizes, and thus, resolutions. There is a difference with systems that have a larger sensor size - less noise when using high ISOs. Expect both camera systems to use AF Contrast Detection and Phase Detection as standard. The real benefits come from the tracking features.
Conclusion
The main benefits of the mirrorless system are the smaller size and weight. You'll notice they also have AF tracking, many more auto focus points and higher burst rates. But, they lose in the wide option of lenses and the battery power doesn’t stretch far enough for some. The lenses can be ‘adapted’, and technology will soon extend battery life. Thankfully, these systems are REAL silent shooters, and built with handheld photography in mind.
DSLRs are the powerhouse of the digital camera world, used professionally for decades. They have been improved thoroughly but will eventually lose as the heart of their system is limiting. You can’t get faster, smaller, quieter or lighter with a huge mirror in the way. Personally, I prefer a mechanical shutter to an electronic one for framing a shot. This outweighs the helpful burst rates (who needs 30fps?!)
What will be interesting is how many DSLRs will no longer be improved in the years to come. As mirrorless systems and camera phones gain more attention, they will continue to take up the slack.