What do DSLR and mirrorless cameras mean? What's the difference?

I, meaning

1, SLR camera

It refers to a single lens, and the light through the lens to the reflector, through the reflection of the camera.

The so-called "single lens" refers to the photographic exposure optical path and the optical path of the view **** with a lens, unlike the side axis camera or dual-lens reflex camera as the view of the optical path of a separate lens.

"Reflective" means that a flat reflector in the camera separates the two light paths: when framing, the reflector falls down, reflecting the light from the lens to the pentaprism, and then to the viewfinder window; when shooting, the reflector lifts up quickly so that the light can reach the film or the sensor CMOS or CCD.

2, mirrorless cameras

Reflectionless cameras are mirrorless cameras, also known as semi-lens cameras.

As early as in the film SLR camera period, Canon and other optical manufacturers have designed the use of half-lens technology mirrorless, the intention is in fact to want to eliminate the traditional SLR plate up and down the movement of vibration, delay, viewfinder black time is too long, and other unfavorable factors in the ultra-high-speed continuous shooting.

Two, the difference

1, phase focus is different

SLR adopts an independent phase focus module, so it still has to retain the reflector structure. Phase focus is more reliable and stable, and very fast.

And mirrorless cameras use contrast focusing, which works much like a two-dimensional scan of the scene and selects the more contrasting areas to focus on, so this method is currently less fast and stable compared to phase focusing, especially when shooting dynamic and small objects.

2, different from the way of viewfinder

DSLR cameras can choose to use the optical viewfinder or LCD screen viewfinder. Optical viewfinder is directly through the lens viewfinder, light from the lens, through a reflector, refracted to the focusing screen above the image, and then refracted to the eyepiece.

Mirrorless cameras, on the other hand, can only be viewed electronically using either an LCD screen or an electronic viewfinder. Electronic viewfinders are intuitive and can simulate exposure effects while viewing the scene, but the image can become rough in low light.

3, different size

DSLR cameras are relatively large in size, because they require a more complex camera structure, but also because of the structure of the mirror and can not further reduce the body size.

Mirrorless cameras are lighter, due to the elimination of the reflector and pentaprism (five-faceted mirror) structure, so the volume of the body has been greatly reduced, and portability is greatly improved.

Baidu Encyclopedia - Mirrorless Camera

Baidu Encyclopedia - Single Lens Reflex Camera