Arts & Culture

DSLR vs Mirrorless, the Next Evolution

The camera industry is undergoing a great new evolution. The shift from DSLRs, or digital single-lens reflex cameras, to mirrorless might just be the biggest change since the switch from film to digital twenty years ago. SLRs, or single-lens reflex cameras, were invented in the early 1880s. Ranging from entry level to high-end professional models, it became the mainstream camera design in the 1960s and dominated the camera industry for almost sixty years. But now, a new camera design is ready to take its place, namely the mirrorless camera.

To begin with, what are DSLRs and mirrorless? DSLR is the digital version of SLRs. As shown in the diagram, DSLR has a mirror in the camera body in front of the sensor. It reflects the light coming through the lens into the pentamirror or pentaprism, which then redirects the light to the view finder, the small scope on top of the camera that photographers look through. When taking a picture, the mirror flips up, exposing the image sensor to the light, and the camera captures the image. Mirrorless, on the other hand, does not have the mirror as the name suggests. The light goes directly to the sensor through the lens, and the view is not projected into the view finder. Thus, mirrorless cameras often use an electronic view finder instead of an optical one. It is simply an electronic display that shows what the sensor is seeing. Mirrorless are not limited to professional grade cameras, however. All smartphones, for example, have mirrorless cameras. The view seen by the sensor is directly displayed on the phone screen. A phone is simply too small to fit in a flipping mirror and an optical viewfinder as a DSLR. But, for mirrorless to take on the DSLRs, the comparison has to be between high-end interchangeable lens cameras. Here are a few major aspects for comparison.

A DSLR (left) showing its mirror and a mirrorless (right) directly exposing its sensor

Without the mirror, the size of a mirrorless camera can be reduced significantly. For example, a professional grade DSLR such as the Canon EOS 5D Mark IV has the dimensions of 150.7 x 116.4 x 75.9 mm, but the more advanced mirrorless camera, Canon EOS R5, has a small size of 138 x 97.5 x 88 mm. The compact size benefits all kinds of photographers, allowing them to not carry around a bulky DSLR everywhere. However, a slight disadvantage of the small size is that mirrorless can make the grip less comfortable. Some photographers prefer a deep, firm grip when holding a camera, but the smaller sized grip of a mirrorless can feel less secure. Furthermore, when attached with a heavier lens, a mirrorless camera might become too front-heavy, loosing balance. But nevertheless, the grip can be easily improved, and the benefits of a more compact size overshadows mirrorless’ shortcomings.

The optical viewfinder (OVF) of a DSLR and electrical viewfinder (EVF) of a mirrorless camera each has their own benefits. The OVF shows direct reflection of the view of the camera, so it does not have any delays. The EVF, however, shows an electronic display of the view after being processed by the sensor. Thus, slight delays do occur. But an EVF can display more than just the view. It can show histograms and even give exact preview of the exposure dialed in by the user. Moreover, because the mirror of an SLR has to flip up while taking a picture, the OVF blacks out when releasing the shutter, but the EVF can continue its display at all times. Thus, the preference between OVF and EVF depends on the photographer. Sports or wildlife photographers might choose a DSLR because every split second is important for their work, and they cannot afford to lose any precious moments due to the delays of their viewfinders. On the other hand, others might prefer the EVF for the convenience it brings to exposure.

The autofocusing systems of DSLR and mirrorless are drastically different. Because the mirror has to flip down to show the view in the OVF, blocking the image sensor, DSLR uses Phase Detect autofocus, a separate system with a separate AF sensor located below the mirror, as shown in the diagram. Behind the main mirror is a secondary mirror that reflects the light from the semitransparent areas of the main mirror to the AF sensor. The sensor then processes the information and adjust the focus. A mirrorless camera, on the other hand, autofocuses with its image sensor using On Sensor Phase Detect, since the sensor is always exposed to the light. This enables more processing power. Therefore, mirrorless cameras can achieve features such as face detect autofocus or eye detect autofocus, even for animals. Mirrorless cameras also have wider spread focusing points that can autofocus for a larger field of view. However, the speed and accuracy of DSLR’s Phase Detect autofocus still outperforms the mirrorless, although the gap between their AF performances closes with each new generation of cameras.


Finally, each camera brand has their own lineup up of lenses. For example, Canon’s EF lens mount for film and digital SLRs was introduce back in 1987. The EF series includes over eighty lenses, and in 2014, Canon claims to have produced its hundred-millionth EF lens. Nikon’s F-mount is even older, dating all the way back to 1958. Moreover, with the same lens mounts, old lenses can still work on modern DSLRs. However, camera companies have to abandon their long-standing lens mounts and lineups to develop mirrorless technology. The mirrorless interchangeable-lens cameras are designed with newer, more modern lens mounts and with them, come new lineups of lenses. Canon, for example, developed the RF lens mount for their mirrorless EOS R System, abandoning the thirty-year-old EF mount. Since most camera owners still own lenses from the old SLR systems, camera companies all developed lens mount adapters to ease the transition, allowing old lenses to be attached to new mirrorless cameras. However, cheaper third-party lenses for the new mirrorless lens mounts still haven’t fully developed a lineup yet, limiting the amount of new lens choices. Thus, there is still a period of transition from old to new camera mounts.

Canon’s EOS R System


So what is the future? From the comparisons, it is obvious that mirrorless technology is more advanced and has more potential than DSLRs. Although in some respects, DSLRs still remain superior, but each generation of mirrorless cameras closes up the gap more and more. DSLR technology has reached its limit. Camera industries have begun to abandon their developments and move on to technologies with a greater future. Major companies like Sony already transitioned to fully mirrorless systems. And earlier this year, Canon released the EOS 1DX Mark III, possibly the most powerful DSLR ever but also last of its kind. The company has no future plans for the EF mount nor its DSLR lineup and will begin to focus its full strength on the development of the EOS R System. Although the future of photography belongs to the mirrorless, DSLRs will never be forgotten. Just as some still prefer the analogue film cameras, there will be those who miss the soft “click” of mirrors of the DSLRs.


Works Cited:

“Canon EF Lens Mount.” Wikipedia, Wikimedia Foundation, 15 Nov. 2020,

DIY Photography,×419.jpg.optimal.jpg.

“History of the Single-Lens Reflex Camera.” Wikipedia, Wikimedia Foundation, 18 Sept. 2020,

Ltd, Reikan Technology. “How Does DSLR Auto Focus Work?” Reikan FoCal – About Autofocus,

“Mirrorless vs DSLR Cameras: Which Is Right for You?” Canon Australia, 20 June 2018,

“Nikon F-Mount.” Wikipedia, Wikimedia Foundation, 11 Oct. 2020,

Northrup, Tony and Chelsea Northrup, directors. Mirrorless vs DSLR Cameras. Youtube, 30 Apr. 2017,

Polin, Jared.


Photo of the Month: Black and White Photography

Here are all the amazing submissions from November’s Photo of the Month.

Lockdown Doesn’t Mean You’re Grounded

by Abigail Kusuma

Musee D’Orsay

by Andrew Chen

by Mari Stanton

by Talia Poortenga

Yaks Pose for Cameras Too

by Micah Glorioso

by Peyton Rice


by Laura Cervantez


by Pia O.

by Hannah Ling


by Sophia Thuemmel

by Oliver Munzer

Light Through a Window Frame

by Sarah Hicks


by Rachel Beth H.

by Sophia Twitchell


Next month’s theme is: Christmas

Please submit your photos with this Google Form:

The submission deadline is December 26th. If you have any questions, please let me know in the comment section.


  1. Wow interesting article- my uncle is crazy about photography and has rubbed some of his camera craze on me so this is really cool lol. And nice job on all the pictures!

  2. Great post! And amazing pictures you guys!

  3. rebeckbeckfunfuncakecake

    oooh awesome pictures =D

  4. oouuuu those are some awesooommmeee pictures y’all!

  5. Interesting read Charlie! I just switched from an old DSLR to mirrorless, so it was cool to read described the differences I have experienced. Just curious, but what camera do you use?
    Also POTM submissions were great as always!
    Great job on the drawing and photo Sarah!

  6. omunzer/Oliver Munzer

    *grin* my pic was featured. *face plant*

  7. Awesome job on your black and white photographs, everyone!

  8. ay, great article and awesome photos everyone!

  9. OliverMunzer/omunzer

    hey, i also liked everyone’s photos so much!!!They were so cool! well done!

  10. I have been educated.