If the photos your smartphone takes aren't cutting it once you blow them up to put on your wall or if your old point-and-shoot is camera ready to give up the ghost, you'll want to invest in a removable lens camera system—but what kind? Should you go with a DSLR, or would your money be better spent on a smaller, mirrorless camera system? Each option offers perks that the other can't match. Both camera types are wildly popular with photographers. Which is best?
The good news is that there's no wrong answer to these questions. Modern DSLRs and Mirrorless cameras boast similar image quality and share many of the same features. Which kind of camera system you opt for will likely come down to your budget and a number of details which, if you're new to interchangeable lens cameras, might confuse you or be easy to overlook. Don't worry, we've got your back.
To provide you with the information you'll need to make a fully informed buying decision, we've put together a list of five important differences between mirrorless cameras and DSLR systems. This is complicated stuff, but we've done what we can to keep it as simple as possible. But if you have any questions, let us know.
Design, Weight and Size
Ever notice how every DSLR out there has the same shape? There's a reason for that and it has to do with what's inside of the camera's body.
The SLR in DSLR stands for Single Reflex Lens. At the core of any SLR system, is a prism and mirror. The prism is there to refract light captured by the camera's lens into the DSLR's optical viewfinder so that you can see the image you intend on shooting. When you push a DSLR camera's shutter button, the mirror quickly raises up, allowing the light let in by the camera's lens to reach the image sensor in the camera body. In order to accommodate the Prism, mirror and all of the mechanical tomfoolery required to move the mirror, the body of a DSLR needs to be wide and tall.
In order to refract light into the camera's optical viewfinder, both the prism and the viewfinder need to be correctly orientated. This orientation is the same for any DSLR camera out there, as well as old school film SLRs, too. The prism, mirror and mechanism to move the mirror and other internal parts have a lot of heft to them. This weight various based on the quality of the materials used to make those parts. Higher end DSLRs will come with more rugged exteriors and internal mechanical components. This increases the weight of these already bulky cameras. Less expensive models will use plastics and less durable internal components in a bid to keep the cost and weight of the camera lower.
A Mirrorless camera, as the name implies, has no mirror and, as such, doesn't need a mechanism to move one around. It doesn't come with a prism, either. Instead, the camera's sensor is always exposed to the light captured by the lens attached to the camera's body. This lack of a prism and mirror means that a mirrorless camera body can be designed to be considerably smaller than a DSLR. And, as mirrorless camera systems leverage a display on the rear of the camera body or an electronic viewfinder (we'll talk about that in a minute) instead of a prism and optical viewfinder, there's no limit on where the display or Electronic View Finder (EVF) can be placed. Because of all of this, camera manufacturers have a lot more latitude in how they design mirrorless cameras. This in turn, means more options to consider if you're shopping for one.
Finding Your View
A great photograph is the result of careful planning and knowing how to frame your shot. You can't frame your shot unless you know can see what you're shooting at. Mirrorless cameras and DSLRs approach how they present your subject matter to you in slightly different ways, both of which, have benefits and disadvantages.
As we discussed earlier, a DSLR uses a prism to refract the light captured by the lens attached to it into the camera body's optical viewfinder: In essence, you see what the camera sees. What's nice about this is that, in most cases, you don't need to turn your camera on in order to frame a shot, saving your battery for when it counts. The disadvantage to this is that you won't be able to see what the photo you're going to take will look like before pulling the trigger on it.
This is because with a DSLR can't apply any of your exposure or focus settings to the final image until you've pushed the camera's shutter button, giving it the signal that it's ok for it to shift its mirror so that light can reach its image sensor. This leaves you at the mercy of your camera's light metering and your skills as a photographer. A lot of DSLRs come with a live preview setting that raises the mirror so that you can see the final the results of your photo as you frame it, but this takes extra time, could mean missed photographic opportunities, and battery power.
As light is always pouring over the image sensor of a mirrorless camera, what you see is what you get. You'll see the results of the settings you choose and how they apply to the photo you're taking, in real time, in your EVF or on the camera body's display. Better still, it's possible to overlay real-time information that you can use to ensure the shot you get: focus peaking information, the real-time application of image filters, and other photographic data can all be seen before you click the shutter button.
The downside to using an EVF or relying on the display on the back of your camera body is that both suck in extreme lighting conditions. A camera display can be difficult to see in bright sunlight. And when the lights are low, what you're shooting will appear grainy and discolored, even if the final image isn't. Additionally, this always-on functionality causes more drain on your camera's battery.
If you've used a camera in the past 15 years, you'll have a good idea of what a megapixel is, so we won't waste any time discussing the topic here. Instead, let's jaw about image size and focal length.
While shopping for a digital camera, you may run across the term 'full-frame.' This refers to the fact that the digital sensor inside of the camera is the same size as a piece of OG 35mm film. A full frame sensor is desirable because it provides better low-light performance, and a broader dynamic range (more complex colors and tones.) Unfortunately, full-frame sensors are typically only found in more expensive DSLR hardware. Inexpensive to middle-of-the-road DSLRs as well as mirrorless cameras use what's referred to as a crop sensor—that's shutterbug talk for a smaller image sensor. A smaller sensor means inferior lowlight performance and a restricted dynamic range.
The size of sensor you have in your camera also affects the focal length of whatever lens you attach to it, which in turn affects what you can see when you're framing up a shot. So, if you're using a 35mm lens with a full frame camera, you'll see everything that the lens can see when you're framing your shot and afterward, in the photos you've taken. Take that same lens and use it with a crop frame sensor and you'll see less of what the lens does because there's not as much sensor to take it all in.
Choosing a camera system that uses a crop sensor doesn't mean that you're doomed to take lousy photos. It simply means that you'll capture less of a scene than you might if you were using a one with a full frame sensor. If you can live with this, you'll likely save some money on your camera purchase and you could wind up being very happy with a lightweight, mirrorless camera.
When you own a removable lens camera system, dust and other debris are the enemies. Every time you swap out a lens, you're inviting crud to get into your camera's body. Sooner or later, those particles will wind up in a position to affect your photos.
In the same way that there's nothing between a mirrorless camera's sensor and the light getting into it when you're taking a photo, there's nothing to stop dust and other contaminants from getting on a mirrorless camera's image sensor once you've removed a lens. There's a lot of great guides online that detail how to clean a mirrorless camera sensor, so I won't go into it here. I will however say that, in my experience, while you're more likely to wind up with dust with a mirrorless system than you will while using a DSLR, it's much less of a pain to clean the junk off of a mirrorless camera's sensor than it is to deal with dust and other unwanted elements in a DSLR camera system.
As we discussed earlier, a DSLR has a mirror/shutter that flaps around every time you take a take a photo. When you remove a lens from a DSLR, the shutter will be in the closed position which should protect the image sensor and mirror from dust and debris.
When you attach a new lens to your DSLR body, any dust that's on the shutter, mirror or the lens itself will be trapped between the lens and the camera body. Take a picture and the rapidly moving mirror inside of your DSLR will move the air inside of the camera around which, in turn, can move that dust and other gunk around. Sooner or later, it'll end up on your DSLR's image sensor. Many DSLRs and some mirrorless systems come with a cleaning mode to help bring this issue to heel. When you activate a camera's cleaning mode, the hardware inside of the camera body will attempt to vibrate the dust off of the image sensor. This works a lot of the time. But in some instances, the dust will stay put. Unfortunately, cleaning the image sensor on a DSLR, because of the delicate mechanisms that move the mirror, can be a dicey proposition, best left to professionals. And where ever the word 'professional' gets used, you know that you're going to be out some money.
Speaking of delicate mechanisms, it's worth noting that as there aren't as many moving parts inside of a mirrorless camera system than there are in a DSLR camera body. This means there's less that can go mechanically wrong with it. This could save you money in the long run.
If you live to pimp out your hardware, you're likely going to want a DSLR camera system.
In addition to the first-party lenses that your camera's manufacturer designed specifically for your camera, you'll also find a wide variety of lenses of all types made by aftermarket manufacturers, available at various price points to suit any budget. And that's just the modern models that can be had new in stores or online. Some DSLR cameras can be mated with adapters that'll allow you to use old-school manual focus lenses from film SLR cameras. So, if you have an old SLR kicking around in the back of your closet, it might be worth looking into whether or not the glass can be used with a modern DSLR before pulling the trigger on a purchase. Beyond this, there's a whole sea of flashes, extended batteries, underwater housings, custom cases and other finery that can be had for a DSLR to truly make your camera your own.
While it's absolutely possible to accessorize a mirrorless camera with cases, tripods, gimbals and other expensive finery, you'll find that when compared to the number and kinds of lenses available to DSLR uses, the amount of glass that available for mirrorless cameras to use is pretty limited. In many cases, you'll be limited to buying lenses designed by your camera's manufacturer specifically for use with your camera. There's an upside to this lack of variety, however—buying one of those lenses guarantees that they'll be able to leverage all of the features packed into your camera system.