Should You Buy a Mirrorless Camera or a DSLR Camera?
The two major players in the professional digital camera world today are DSLRs and mirrorless cameras. Both camera types offer a number of advantages and disadvantages that should be considered before deciding on a new camera body. This is because both DSLRs and mirrorless cameras allow the user to change lenses as desired. And because these lenses are not compatible across brands or type of camera, you’re making a commitment with your choice in camera.
Now, you’re not 100% locked into a mirrorless or DSLR brand and lens selection. You can buy adapters for both same-brand and cross-brand lenses. If something special from Canon’s DSLR lens selection would work well with your Nikon DSLR body, there’s a solution. If you have a new Nikon mirrorless camera that would do well with an older Nikon DSLR lens, there are adapters for that as well. But those adapters also have disadvantages, which will be explored in detail below. The vast majority of camera owners stick to a brand and style to keep all functions working perfectly across their gear.
And what capabilities do DSLRs and Mirrorless cameras have to offer? Well, it’s probably best to first determine what each camera type is. And from there, we’ll think about how each of the differences should play into your decision making. Remember, neither style is superior, simply different.
Table of Contents
- What is a DSLR Camera?
- What is a Mirrorless Camera?
- What are the differences between DSLRs and Mirrorless Cameras?
- DSLR Comparative Advantages
- Mirrorless Comparative Advantages
What is a DSLR Camera?
DSLR stands for Digital Single Lens Reflex. The camera is similar in structure to the older, film-based SLR-style camera. Any SLR camera uses a series of mirrors to send light to either the image sensor/film or the viewfinder. The main difference is that a DSLR uses a digital sensor instead of film to capture light and create an image. But the camera has to send light to either the sensor or the viewfinder, not both at the same time.
If you want to look at a subject, a mirror behind the camera’s lens bounces light up into a pentaprism. A pentaprism is a block of glass with five sides, two of them with a mirrored coating. Within the pentaprism, light is reflected twice to in order to be channeled into the viewfinder where your eye can see it. Some DSLRs have a pentamirror, which does the same thing, only using mirrors instead of a solid block of glass. If you like what you see, clicking the shutter makes the mirror behind the lens drop. And light goes straight from the lens onto the image sensor, where an image is recorded.
Most DSLRs also use a mirror-based Phase Detection system to determine AutoFocus. The phase detection system of a DSLR uses a special set of mirrors and an AF sensor separate from the image sensor. The phase detection mirrors split the incoming light into pairs that the AF sensor then analyzes. By determining differences in light intensity between the pair, it can determine how in or out of focus a subject is. The takeaway here, is that DSLRs use a complex system of mirrors and glass to channel light to both a viewfinder and a phase detection AF system. Once you’ve decided on your settings, clicking the shutter sends the light straight to the image sensor to record a photograph.
What is a Mirrorless Camera?
A Mirrorless Camera is pretty self-explanatory, but the minor differences between it and a DSLR add up quickly. As you’d guess, a mirrorless camera does not have internal mirrors to channel light. It’s even more digital than a DSLR. The light entering through the lens hits an image sensor to be recorded, just like a DSLR. However, there are no mirrors directing light to a viewfinder or phase detection system. On a mirrorless camera, you look through an electronic viewfinder. The EVF is a direct feed from the image sensor of what’s in front of you. Any DSLR with a LiveView LCD also can show a digital live image. But the EVF eyepiece on a mirrorless camera is more comfortable for people used to shooting through an optical viewfinder.
Mirrorless cameras rely mostly on Contrast Detection. Contrast detection looks for maximum color contrast in the image the sensor is creating, and adjusts focus until it finds it. A contrast detection sensor will often pan in and out of focus to find the precise point of maximum focus. It’s generally slower, but also more accurate than a phase detection sensor. Due to the need to pan in and out of focus, moving subjects can give contrast detection sensors a harder time. Mirrorless cameras pioneered the hybrid AF system to compensate for this. It uses the speed of phase detection with a final contrast detection check to lock in focus. To summarize: the sensor of a mirrorless camera does triple duty compared to a DSLR. It’s your viewfinder, image sensor, and autofocus sensor all-in-one. This greatly reduces the size of the camera’s body.
What are the differences between DSLRs and Mirrorless Cameras?
This is one of the most obvious differences between the two types, and a huge reason to go mirrorless. DSLRs tend to weigh more than mirrorless cameras with a similar price and features. Nikon’s D3300 DSLR is considered fairly light at 430 grams. Sony’s a6000 has comparable features and weighs 344 grams. The styling of the cameras are also vastly different. The D3300 is not an especially large DSLR, but it’s noticeably bulky. If you’re out with it, it’s either around your neck, in your hands, or it needs to be stowed out of the way. With the a6000, after you remove the lens, you can slip it into a pocket. Not all mirrorless cameras are pocket sized like the a6000, but they’re all significantly more compact than their DSLR counterparts.
However, sometimes we want a larger body. The grip of the camera can feel more secure, as does the added weight. And it even affects our, and a potential client’s, perception of what it means to be a photographer. Sometimes a photographer bidding on a shoot at a wedding or studio will be taken less seriously with a “tiny” camera. People who don’t know, think “big and bulky equals expensive and better,” whether it’s true or not. And satisfaction in using the camera is a big part as well. If portability and convenience matters, a smaller body might be right for you. If you want to feel like a photographer, a larger body might be ideal.
DSLR bodies were designed to be usable with original SLR style lenses. Nikon’s F-mount series goes all the way back to 1959, for example. This is an advantage, as the selection of DSLR lenses is extremely diverse. Other manufacturers like Canon, changed their mounts but provide adapters to use older lenses with their newer DSLRs. But this is also another reason why it’s hard to slim down a DSLR. To keep a DSLR body usable with older SLR lenses, certain limitations apply. For example, flange length has to remain constant. Flange length is the distance from the base of an attached lens to a camera sensor/film. A lens is designed specifically for a certain flange length. And it cannot be used with a body with a different flange length.
Flange length is also the reason why DSLR lenses can be retrofitted to work on mirrorless cameras but not the reverse. A mirrorless camera has a shorter flange length compared to a DSLR. Buying a DSLR adapter allows a lens to properly connect and lock to the mirrorless body. But it also creates a larger gap between the lens and sensor so the flange length is the same as a DSLR body. A mirrorless lens is designed for a smaller flange length. So adding an adapter to a mirrorless lens would simply make the gap larger, when it needs to be made smaller. Mirrorless cameras can reap the benefits of the DSLR lens selection, but not the other way around.
But while people often say adapters make the differences in lens variety moot, there are disadvantages as well. Coupling lenses across types or brands usually means you lose the ability to use autofocus and auto aperture. Aperture is how wide the lens can open to let in light, and is a key element of photography. The adapter can’t translate signals from the camera body to the aperture or AF motors of the lens, so you have to do it yourself. And adaptors are an additional expense and piece of equipment to carry around. If you already own a lens collection from one brand, an adapter might be a great purchase. But if you’re starting fresh, there’s little reason not to stick to a single brand. Every brand has a wide enough selection of lenses to cover all sorts of shooting settings and scenes.
Olympus and Panasonic are a special case in cross branding: their mirrorless cameras use a sensor sized at “Micro 4/3rds.”They also use the same mount for their lenses, so their mirrorless lenses are compatible across both brands. However, both brands have differences in image stabilization and other features that may require you to use same brand body and lens to get the full effect. So do your research before buying an Olympus or Panasonic solely for this reason.
There’s a lot of hype and misinformation regarding the autofocus capacity of DSLRs and Mirrorless cameras. DSLRs are thought of as phase detection based, and mirrorless as contrast detection based. DSLR mirror-based phase detection is generally faster as the AF system has its own separate mirror and sensor system to determine focus. On a mirrorless camera, the image sensor also acts as the contrast detection AF system, which can slow things down.
However, the truth is that there are few generalizations to make here. Both mirrorless and DSLRs have hybrid AF models that use both contrast and phase detection. Hybrid AF cameras are both fast and accurate. They use phase detection to get approximate focus, and then switch to contrast detection for accuracy. Mirrorless cameras do tend to have hybrid AF systems for a lower price than DSLRs. And having fast, accurate hybrid AF in a smaller body is definitely attractive.
The most important thing is to understand the difference between the two systems. And to know which type of autofocus your camera has, and if it’s enough for your needs. If you’re looking for fast action photography, speed is essential. A DSLR with a dedicated phase detection system or a DSLR/mirrorless hybrid AF system is what you want when speed is important. Contrast detection works nicely for portraits and macro photography because your subject is not moving rapidly within the scene. The slower autofocus speed and subject tracking difficulties are not important compared to focus accuracy. So choose what’s right for what you plan to shoot the most of.
Shutter Speed and Continuous Shooting
How fast and how many images per second can the camera take? For once, we have a distinct advantage for the mirrorless category. Mirrorless cameras have a regular shutter like a DSLR. But many can also employ an electronic shutter that’s not only incredibly fast, but entirely silent if desired. The Canon EOS 5D Mark IV, a top quality DSLR, can snap as fast as 1/8,000ths of a second. And it takes 7 images per second in continuous shooting mode. The much cheaper but still high-end mirrorless Olympus OM-D E-M1 Mark II can snap 1/32,000ths of a second. It can also take 60 images per second with continuous shooting mode. Both can be used in sports photography, but mirrorless cameras bring a lot more speed to freeze the action. And the Silent Mode most mirrorless cameras offer, is great when you’re looking to not stand out with loud clicks.
Let’s cut to the chase. There’s no difference in image quality between the two types. None. It all depends on a ton of variables. What sort of lenses you’re willing to pay for plays into it. So does sensor size, megapixel count, what sort of photography you’re doing, your own skill, and more. But especially your own skill with the camera. And there’s so much crossover in features between the two types that it’s a wash. The sensors are still CMOS technology, whether DSLR or mirrorless, so the two types remain close cousins, rather than radically different technologies.
Mirrorless cameras have far fewer options in the full-frame category of cameras, which are often important to professional shooters. Full-frame sensors are sized the same as 35mm film. These are the largest sensors commonly offered, and don’t pre-crop the field of view compared to 35 mm film. APS-C, Micro 4/3rds, and anything else, will create a smaller (cropped) field of view compared to the same scene taken by a full-frame camera. Also, the larger the sensor, the higher the dynamic range is (the range of colors captured). Image noise at all levels of sensor sensitivity is reduced by having a larger sensor as well. The vast majority of both mirrorless and DSLRs have sensors smaller than full-frame. But it’s also true that there are more full-frame DSLR cameras than mirrorless cameras, for now. Many photographers prefer full-frame sensors, so having a greater selection with DSLRs might affect your decision.
Image Stabilization is found in either the camera’s body or lens. It corrects for motions due to the shutter press or the photographer that could cause blur in the photo. In-lens IS, which most DSLR users have access to, adds a bit of weight to a lens and the entire setup. Also, it’s only good for that single lens. However, at maximum lens zoom, in-lens IS will work better as the extended lens is much more sensitive to movement.
Most mid to high priced mirrorless cameras have in-body IS that is effective and adds no extra weight. In-body IS also means you have image stabilization with every lens you use. The main reason DSLRs don’t usually have in-body IS is because most manufacturers already have a huge selection of IS lenses. A few of the newer model DSLRs have in-body IS as well. But for now, in-lens image stabilization is the most familiar and popular version among DSLR users.
Live View and Electronic Viewfinder
The LiveVew LCD and electronic viewfinder all mirrorless cameras have, are very useful. LiveView allows you to see how your picture should turn out with the settings you’re using. All DSLRs have an LCD, but LiveView is not found on every one of them. Most DSLR LCD screens display your settings and shows the image you’ve taken. But using LiveView to get the shot right the first time is a great time saver. Without it, you’ll often snap, look at the resulting image, then adjust and snap again. Some mirrorless cameras also tweak the EVF with additional features such as focus peaking, which colors in the areas in sharp focus. The smart view of mirrorless EVFs are a powerful advantage the optical viewfinder of DSLRs don’t have.
The flip side is that in very poor lighting, the mirror-using viewfinder system of a DSLR remains accurate. The LiveView or electronic viewfinder of a mirrorless camera can struggle a bit in these settings. The frames per second of the EVF display slows down as the camera allows more light per frame. The resulting image will look less smooth, and even slightly blurry. Also, cheaper mirrorless cameras often have a noticeable delay in the EVF display. If you move the camera, it will take a moment for the display to catch up. Middle to high end mirrorless cameras have excellent EVF systems that are rarely challenged by lighting levels or movement. But even a cheap DSLR optical viewfinder will produce an instant, accurate view of your subject with its system of mirrors.
DSLRs are a clear winner in this category. The body of a DSLR is larger due to the complex mirror systems. This creates a lot of space for a battery to be housed. The compactness of mirrorless cameras is a great advantage. However, the batteries are smaller as well. A low priced DSLR like the Nikon D3400 can shoot 1200 images per charge, and most sit around 900 to 1100. Mirrorless cameras tend to range from 250 to 400 images per charge.
Both styles have models that are higher or lower than these averages. But as a whole, DSLRs have a lot more shooting stamina. Another reason mirrorless cameras draw more energy is because of the electronic viewfinder and LCD panel. The pentaprism/pentamirror system of a DSLR viewfinder is entirely passive and uses no power whatsoever to display the subject. Extra batteries are not incredibly expensive, but they’re more of a luxury for a DSLR owner versus an absolute necessity for a mirrorless user.
DSLR Comparative Advantages
- Much Higher Battery Life
- Larger Native Lens selection
- Slightly Faster Autofocus speed with dedicated Phase Detection system. Phase Detection is fast and works well with moving subjects. DSLRs with Hybrid AF systems are fast and accurate.
- Optical Viewfinder (consumes no power and the view is a reflection of your subject)
- Larger Selection of Camera Bodies
- In-Lens Image Stabilization is most common (better when using maximum lens zoom)
Related: The Best DSLR Cameras Under $500
Mirrorless Comparative Advantages
- Lighter Weight and Smaller Body Size
- Faster Maximum Shutter Speed and Continuous Shooting. Can also use a silent shutter.
- Better Autofocus accuracy with Contrast Detection. Contrast Detection is accurate and works better with slower or still subjects. Mirrorless cameras with Hybrid AF systems are fast and accurate.
- Electronic Viewfinder (gives enhanced digital view of the subject)
- LiveView LCD found on all models (allows photographer to see how image will look before taking photo)
- In-Body Image Stabilization more common (better if you already have a large lens collection)
The two camera types have significant differences, but to say either is better or worse simply can’t be done. Instead, it’s better to highlight the key strengths of each type to help you decide which has the features you want. Image quality, price, features, and ease of use all depend on the brand, model, and what kind of photography the user wants. If you don’t do a lot of sports photography, a shutter speed of 1/32,000ths of a second is not very useful. If you are very casual about your photography, high battery life might not be important to you. So choose the strengths that best suit your needs as a photographer. Happy shooting!