What Are Mirrorless Cameras?

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Capturing a moment requires a few things: the perfect light, captivating ambience, and a bit of creativity. With those three factors, you’re all set to wander artistic trails down memory lane, pondering the power of the past. 

A photograph is often a powerful medium to influence large groups of people. Certain photographs can tap into emotional revelations deep in your memory, a sentiment that is far more profound than merely observing a recorded point in time. You might know the truth behind a photograph, but you don’t necessarily know how it will make you feel. 

That reaction all depends on the adroitness of the photographer, namely how well he or she can present “that scenic pause of a lifetime”. Along with creativity and the perfect setting, the camera is a rather critical element in the process. Regardless of how marvelous your potential subject may be, a camera that cannot capture what your eye perceives is simply no good.

Hand holding a wooden frame on sunrise sky background. Care, safety, memory or painting concept. - Image( A. and I. Kruk)s

Capturing a moment (Photo Credit: A. and I. Kruk/Shutterstock)

With significant improvements in optical technology, digital photographs have done away with the “good old” film reel, leading to much better results in every pixel you captured, despite eliminating the exhilaration of getting the negatives developed and revealing the moment you had masterfully seized. Of course, every camera has its benefits, and this article is not intended to promote any brand or category of cameras. That being said, the modern-day DSLR has a new technological competitor in the market—Mirrorless Interchangeable-Lens Cameras. 

DSLR – Digital Single-Lens Reflex Camera

DSLR cameras are a category of digital cameras that use a mirror mechanism to either A) reflect the inbound light from a camera lens to an optical viewfinder, also known as “the eyepiece”, at the back of the camera, or B) let the light pass onto the image sensor by the rapid upward movement of the mirror to get out of the way.

DSLR cameras have ruled the photography industry for well over ten years now, delivering high-quality images with easily editable files. However, the bulk of the camera body itself, along with the hefty lenses, flash, tripod, and microphone units for videography, posed rather serious obstacles to photographers. Wildlife photography, for instance, demands serious stealth and agility to capture a truly “perfect” shot, and DSLR cameras, despite their quality, are a bit ungainly.

Modern digital DSLR camera and computer workstation. Photography and videography concept. - Image( REDPIXEL.PL)s

DSLRs usually have a big body. (Photo Credit: REDPIXEL.PL/Shutterstock)

So… why is the DSLR body such a big unit?

If you take a look at its mechanism, you will realize that the significant girth of the camera body comes from the prism used to reflect light from the lens to the eyepiece and the mirror mechanism. Although equipped with a screen for displaying the captured shot (unlike our film roll cameras), photographers tend to use the eyepiece to view the scene. Thus, the viewfinder becomes an essential requirement for the photographer’s style of shooting, but does the optical viewfinder show exactly how the final image captured by the camera will look? Certainly not!

This exact reason led to the birth of mirrorless interchangeable-lens cameras with electronic viewfinders. However, before that, take a look at the various components and functions of a modern-day DSLR in the video below:

Mirrorless DSLR

Also known as Compact System Cameras or EVIL (Electronic Viewfinder, Interchangeable Lens), these can be regarded as the natural successor to DSLRs, along with a few technological and necessary changes. 

They are compact, easy to carry, lightweight and most importantly, the image quality is equivalent to that of a DSLR. The camera’s body houses a socket for interchangeable lenses, which are common for both categories of cameras. So, what allows a mirrorless camera to shed the hefty bulk of a DSLR?

Mirrorless camera

A mirrorless camera has no mirror or prism, thus reducing the main bulk of its body.

While a DSLR camera uses a mirror mechanism to reflect light into the optical viewfinder or allow it to directly strike the camera sensor, a mirrorless camera has no such arrangement (hence the name). As a result, the light passing through the lens will always end up on the camera sensor, rather than the viewfinder. This helps to eliminate the massive prism too! With that min mind, you may wonder… what’s the use of the viewfinder on mirrorless DSLR cameras?

Since a mirror is no longer reflecting light to the eyepiece, mirrorless cameras rely on Electronic Viewfinders (EVF) to show what the display screens are capturing on the sensor. After all, the final photograph that gets stored in the camera is what gets displayed on screens, after the final processing of the image. It makes sense to project the final image in the EVF, rather than seeing a different image altogether, which is what occurs in DSLRs.

Close up, Yong man asian photographer holding digital camera mirrorless with lens equipment for take a photo and picture memories travel landscape trip lifestyle. - Image(Zodiacphoto)s

A mirrorless camera. (Photo Credit : Zodiacphoto/Shutterstock)

This simple use of technology has helped to replace two of the major components (the mirror and the prism) of these high-functioning machines.

Benefits of Mirrorless technology

When this mirrorless tech was newly introduced in the photography world, the display on the EVF involved slightly delayed responses and significantly lower resolution than what one would find on an optical viewfinder. That is the primary reason these cameras were developed, despite not surpassing the DSLRs in terms of quality.

Soon enough, camera companies investing in mirrorless technology decided to address some of the main issues. The modern electronic viewfinder displays have almost zero lag, along with incredibly fast processors backing up their motherboards, as well as the benefit of previewing the added effects from the camera settings directly in the eyepiece, which is more aligned with the old school techniques of photography. 

The only downside of using a mirrorless camera is the extra power eaten up by the electronic viewfinder, which reduces the number of shots in a single charge, as compared to modern DSLRs. However, this is the only real issue you will have with this beautiful piece of tech. 

mirror less camera

The Olympus OMD EM5 Mark II is a dust-proof, splash-proof and extremely lightweight mirrorless camera, a perfect go-to camera for wildlife and fireworks photography (Photo Credit: Flickr)

The significant benefits of new cameras going mirrorless:

  • Camera bodies are consequentially smaller and boast a lighter bodyweight than normal DSLRs
  • There is more scope for companies to experiment in higher-speed burst modes, which helps capture rapid movements with greater ease and precision.
  • DSLR lenses, due to their much longer presence in the market, are more trusted and adapted to photographers. Luckily, DSLR lenses can even be adapted for use on mirrorless bodies, although the reverse is not possible.
  • The Electronic Viewfinder can be used in video mode as well, unlike the optical viewfinder of a DSLR.


  1. BBC
  2. ResearchGate
  3. University Of Houston
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About the Author:

Dev is an undergraduate (Bachelor of Science) from St. Xavier’s College (India). He watches a lot of anime and documentaries on the universe and wildlife. He spends most of his time engaging in sports and exercise. He has represented his state at the National Volleyball tournament, in India. Along with that, he has a flair for sketching, photography and would be glad to take up gardening as a career.

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