How Do MILC Cameras Differ from DSLRs?
DSLRs, which have been a favorite among photographers for decades, rely on a mirror mechanism that originated during the film era. This mechanism allows photographers to view the image they are about to capture through a pentaprism or a pentamirror. However, as technology has advanced, mirrorless cameras (MILC) have emerged, presenting their own set of unique characteristics and benefits.
Understanding the Mirror Mechanism in DSLRs
The mirror mechanism in DSLRs derives from the film era. When a shot is taken, the mirror flips up to expose the sensor, allowing light to reach it. This mirror mechanism works in tandem with a focusing screen, ensuring that the light is reflected to the same distance as the sensor. The user views the image through a pentaprism in higher-end models, or through a hollow pentamirror in more basic models. In reality, some light passes the mirror and is directed to the AF sensors for autofocus operation. It is worth noting that due to the mirror mechanism, the user never sees the actual image that will be captured; the view is blocked until the mirror flips up. In practical terms, this means that photographers can only check the preview after the shot, while in the film era, the image was visible only after the film was developed.
Since the advent of digital technology around 2008, DSLRs have had a live view mode. In this mode, the mirror is flipped up, and the viewfinder image is formed using the sensor. For live view to function, the DSLR doesn't need an electronic viewfinder; the image is displayed on the back display instead. It is important to mention that this is the only mode in which video can be shot on a DSLR.
Introduction of Mirrorless Cameras
Mirrorless cameras, which owe their name to the absence of a mirror and a pentaprism, operate similarly to DSLRs in live view mode. Some models feature a display on the back, while others have an electronic viewfinder or an additional viewfinder attached to the flash shoe. The absence of a mirror allows these cameras to be more compact and to have lenses mounted closer to the sensor. On DSLRs, the distance from the mount to the sensor is approximately 45 mm, but in mirrorless cameras, this distance is reduced to about 18 mm. This design not only makes the camera more compact but also facilitates the design of better lenses, especially for wide-angle photography.
Mirrorless cameras can also use DSLR lenses of the same manufacturer with a lens adapter. Furthermore, other DSLR/SLR lenses can often be adapted, including older manual lenses. This is a significant advantage because it means that photographers can still use their favorite lenses with the new mirrorless cameras.
The first mirrorless system, Micro 4/3 by Olympus and Panasonic, has seen its future become highly questionable. Sony introduced its E-mount, and in fact, it only manufactures mirrorless cameras. Nikon introduced its Z-mount in 2018, which is used on both full-frame and APS-C bodies. Canon has a somewhat strange situation: it has the EF-M mount introduced in 2012 for APS-C and the R-mount introduced in 2018 for full frame. These mounts are completely incompatible but both can use all EF and EF-S lenses made for DSLRs and SLRs with an appropriate adapter.
Drawbacks of Mirrorless Cameras
The most obvious drawback of mirrorless cameras is the battery life. Creating the viewfinder image consumes power, and as a result, mirrorless cameras often have shorter battery lives compared to DSLRs. For instance, a Canon EOS 800D can capture around 800 images on a charge, while the mirrorless EOS M6 Mark II only manages 305 images with the same battery. Historically, focusing speed was a major issue with mirrorless cameras, leading to slower performance compared to DSLRs. However, modern sensors have significantly closed this gap. The ability to position focusing points almost anywhere on the sensor also provides mirrorless cameras with a potential edge over DSLRs, especially during live view shooting.
Overall, while DSLRs remain a powerful and traditional choice, mirrorless cameras present an innovative and efficient alternative. As technology continues to evolve, it remains to be seen how these two camera types will coexist and evolve in the future.