Mirrorless Camera Guide
Mirrorless digital cameras are usually mid-size cameras supporting interchangeable lenses. They are system cameras and each model gives access to a set of compatible lenses. In this guide to mirrorless cameras, you will learn what these cameras are good for, plus how mirrorless systems presently compare. There are much more differences between mirrorless system than DSLR systems, so it is critical to consider both the camera and system before buying.
A mirrorless camera is an interchangeable lens camera without a reflex mirror, the same way that a car is a horseless carriage. Until the appearance of mirrorless cameras, digital cameras with interchangeable lenses were all DSLRs which are defined by having a single lens and a reflex mirror to reflect light towards an optical viewfinder. Mirrorless cameras still have a single lens but no optical viewfinder. The original term, SLD which stands for Single Lens Digital, was easy to confuse and therefore the more descriptive mirrorless name was broadly adopted.
While compact cameras were always appreciated for their size, the same could not be said about their image quality. Meanwhile, DSLRs that consistently deliver excellent image quality are frequently abandoned because of their bulk. Mirrorless cameras were invented to produce high quality images from a compact camera.
Mirrorless Image Quality
The high image-quality traditionally exclusive to DSLRs comes from their large imaging sensors which gather more light than those of compact cameras. Mirrorless cameras currently have sensors of various sizes, from compact-size 1/2.3" ones, all the way to the same full-frame size used by top-of-the-line DSLRs. Image quality varies accordingly, hence there is a greater discrepancy between mirrorless systems than among DSLRs.
The diagram shown on the right displays sensor sizes used in current mirrorless cameras. All rectangles are to scale and even coincide with actual sizes on most computer displays. There are actually two very similar variants of APS-C with the one used by Canon being fractionally smaller.
There are now several full-frame mirrorless digital cameras with resolutions ranging from 12 to 36 MP. Most are relatively compact, while some are just as large as a high-end DSLR. All these produce image-quality comparable to modern full-frame DSLRs.
Mirrorless Camera Size
The size of mirrorless cameras varies equally widely. Despite being called relatively compact and having official measurements similar to compact cameras, mirrorless cameras take on bulk once a lens in mounted. Once ready to shoot, most mirrorless cameras are the size of a typical ultra-zoom, only with higher image-quality and a shorter zoom range.
A camera's sensor-size influences its operational-size because larger sensors require larger lenses. As image quality gets closer to that of a DSLR, so does total size. However, there are so many variables involved that there is no simple relation between image-quality and total-size. Slightly wide to medium focal-length lenses give the most advantage, while telephoto lenses tend to even the gap.
Mirrorless vs DSLR
Mirrorless cameras are evolving faster than any other type of digital cameras. Being the youngest type of digital camera increases chances for smaller companies to take the lead, so more manufacturers are trying. The speed of this evolution plus tremendous variations among mirrorless cameras means that there are also plenty of misconceptions.
Top 10 Mirrorless Camera Facts
- Image quality from the best mirrorless cameras is comparable to that of a DSLR using a sensor of the same size. The latest Micro Four-Thirds cameras even produce output which is very close for common print sizes until moderately high ISOs when compared with typical APS-C DSLRs.
- A lens influences the image quality of a mirrorless camera just as it does for a DSLR. To get the best out of a mirrorless, a sufficiently good lens must be used. The typical kit zoom lens sold with cameras is generally built for compactness rather than quality. Often a better kit with a prime lens is offered too.
- In good light, mirrorless cameras are capable of focusing as quickly as mid-range DSLRs. Autofocus performance drops in low-light, as it does for a DSLR, but the gap widens in terms of speed. Accuracy and sensitivity remain comparable though, at least among recent mirrorless offerings.
- Shooting speed of mirrorless cameras exceeds that of the fastest DSLRs. Continuous shooting up to 60 FPS or 15 FPS with continuous autofocus are available at full-resolution and so are shutter-speeds exceeding 1/8000s.
- Mirrorless cameras are quieter than DSLRs because they do not have a reflex mirror to move between shots. Some use an electronic shutter which makes them nearly silent. This is highly advantageous when shooting in quiet environments.
- The preview on a mirrorless camera is electronic, just like a fixed-lens digital camera or Live-View on a DSLR. The preview varies considerably in terms of sharpness and accuracy between models. The best offer a sharp Exposure-Priority display and EVF. When resolution is too low, it is hard to confirm focus. When the update rate is slow, following action is difficult.
- Mirrorless cameras are power-hungry because their sensor must constantly feed the digital preview. Plus, mirrorless cameras are often fitted with smaller batteries. As a result, the average battery-life comes to 359 shots-per-charge, compared to 912 for DSLRs.*Based on current models as of February 2015.
- Mirrorless cameras are strong in terms of video features. It is possible to shoot video with the camera at eye-level and continuously autofocus while recording, either by on-sensor Phase-Detection or highly optimized Contrast-Detect processors and lenses.
- Plenty of mirrorless cameras are now aimed at professional photographers. Those provide high-end features and controls, including dual or even triple control-dials. While a number are weatherproof and freezeproof, such native lenses are rare. At the extreme though, there is a waterproof mirrorless while no such DSLR exists.
- Lenses mount closer to the sensor on mostExcept for Sony SLT and Pentax K mirrorless models. mirrorless cameras compared to DSLRs. This makes them more adaptable to use legacy lenses, although features such as autofocus are often lost.
SLT - Mirrorless with Pellicle Mirror
Sony makes cameras the size and shape of DSLRs which use the same sensors and lenses. They call these SLT cameras for Single Lens Translucent. They use a semi-transparent mirror to reflect around 30% of light to focus and metering sensors. Contrarily to an SLR, an SLT has an EVF. This viewfinder can preview exposure, color, white-balance and focus, up to its maximum resolution.
All current mirrorless models provide a number of advanced features, although their accessibility greatly differs. Particularly, all of them include: full manual-controls, manual focusing, custom white-balance, continuous drive and full 1080p HD video capture. Most models also sport a hot-shoe. They all offer a wide range of shutter-speeds, at least matching those of entry-level DSLRs, but most often exceeding them.
The high-speed CMOS sensor and continuous Live-View allows mirrorless cameras to provide features usually unavailable to DSLRs. This includes sweeping panorama capture and shooting of images in multiple aspect-ratios which only a handful of DSLRs can do.
Manual focusing has traditionally been difficult with anything other than an optical reflex viewfinder. However, the majority of mirrorless cameras offer a Manual Focus Assist function which magnifies part of the image to make manual focusing easier. A few add something called Focus-Peaking which highlights edges of in-focus areas, something which is impossible to do with an OVF.
As with all interchangeable lens cameras, the aperture range and minimum focus distance of mirrorless ones is determined by the lens being used. Most lenses support screw-on filters to modify incoming light.
Flash, either built-in or add-on, is limited by a sync-speed just like it is on DSLRs because all current mirrorless cameras use a focal-plane shutter and electronic shutters are still relatively slow. Expect sync-speeds between 1/60 and 1/250s.
Mirrorless cameras have taken video capabilities to the next level. Some can capture Ultra-HD 4K video and record it directly to a memory-card. The leading models can provide clean 4K or 1080p HD output, including embedded timecode. Ultra-high-speed and slow-motion video recording is also quite common with frame-rates from 2 to 1200 FPS.
Proceed to Step 2 to learn about Mirrorless Camera Systems from each manufacturer. There we compare what each brand has to offer considering cameras and lenses as a system.
New Cameras & Lenses
Fuji Fujinon XF 80mm F/2.8R LM OIS MacroStabilization & Weatherproof
Fujifilm X Mount Prime Lens
Fuji Fujinon GF 45mm F/2.8R WRWeatherproof
Fujifilm GF Mount Prime Lens
Fuji X-E324 Megapixels Mirrorless
Fujifilm X Lens Mount
Olympus OM-D E-M10 Mark III16 Megapixels Mirrorless
Micro Four-Thirds Lens Mount
Canon TS-E 135mm F/4L MacroCanon EF Mount Prime Lens
Canon TS-E 90mm F/2.8L MacroCanon EF Mount Prime Lens
Fujifilm GFX-50S In-Depth Review
In-depth review of the Fujifilm GFX-50S Medium Format Mirrorless Digital Camera, a groundbreaking 50 megapixels camera with large 44x33mm sensor and unique modular EVF system. ISO 50-102400 range, 3 FPS drive and 1080p video.
Fujinon GFX Lens Roundup
Roundup of reviews for GFX Medium Format Mirrorless lenses: Fujinon GF 23mm F/4R LM WR, GF 32-64mm F/4R LM WR and GF 110mm F/2R LM WR.
Nikon D500 Review
Full-review of the ultimate Nikon flagship APS-C DSLR. The Nikon D500 offers a new 20 MP CMOS sensor with incredible ISO 50-1638400, 10 FPS, 4K Ultra-HD and a 153-Point Phase-Detect AF system sensitive to -4 EV. Built for professionals into a weatherproof body with dual control-dials and large 100% coverage viewfinder with built-in shutter.
DxO ViewPoint 3 Review
Review of DxO ViewPoint 3. Perspective, distortion and horizon correction software.
Nikon D5 XQD Review
Nikon flagship professional DSLR with 20 megapixels Full-Frame CMOS sensor. All-new 153-point Phase-Detect AF sensitive to -4 EV. ISO 50 to unprecedented 3,276,800! 12 FPS Drive for 200 JPEGs or 180 RAW. First Nikon DSLR with 4K Ultra HD video.
Olympus Professional Lens Roundup
Roundup of Olympus Professional and Premium lenses: M.Zuiko 7-14mm F/2.8 PRO, M.Zuiko 12-40mm F/2.8 PRO, M.Zuiko 40-150mm F/2.8 PRO, M.Zuiko 12mm F/2, M.Zuiko 60mm F/2.8 Macro.
Olympus OM-D E-M10 Mark II Review
Olympus second generation base OM-D with an anti-alias-filter-free 16 MP Four-Thirds CMOS sensor mounted on a 5-axis in-body stabilization system. Speedy 8.5 FPS drive, full HD @ 60 FPS and a wealth of features in a compact and lightweight body. Offers a 2.4 MP 0.45" EVF with 0.62X magnification and 100% coverage, plus dual control-dials and a highly customizable interface.
Fuji X-Pro2 Review
Fuji flagship XF-mount mirrorless with 24 MP APS-C X-Trans CMOS III sensor. 273-Point AF with 169 Phase-Detect points. 8 FPS Drive, 1080p video. Dual control-dials, direct dials and a hybrid viewfinder in a weather-sealed freezeproof body.
Panasonic Lumix DMC-ZS100 Review
The only premium travel-zoom! 20 megapixels 1" high-speed CMOS sensor paired with a stabilized 25-250mm F/2.8-5.9 optical zoom. 50 FPS Drive, 4K Ultra-HD video, 1/16000-60s Hybrid Shutter, Post-Shot Focus, 4K Live-Cropping, Time-Lapse Video and more. Dual control-dials plus a built-in EVF with Eye-Start sensor.
Canon EOS Rebel T6s Review
Newly designed Rebel with dual control-dials and top status LCD. 24 MP APS-C sensor, Hybrid AF III with 19 all-cross points and on-sensor Phase-Detect AF. 5 FPS Drive and full 1080p HD video capture.