Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
The focus motor moves the lens in order to autofocus. For system cameras, having a focus motor in the camera's body allows you to use a wide range of lenses, including lenses which do not have their own focus motor. For compact cameras, a focus motor is usually built-in.
We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
With 100% coverage, you can compose the image correctly when you capture the photo. With less than full coverage, you may have to crop your photos afterward to get them looking perfect.
Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
An optical viewfinder (or OVF) allows the photographer to compose a shot while seeing exactly what the lens will capture. OVFs have no time lag and require no power - as opposed to electronic viewfinders, which can drain battery life. OVFs are also better in low light situations.
The more focus points the more flexibility in picking which part of the scene to focus on. They also give the image sensor a better probability in identifying the right area of the scene to focus on in more automatic modes.
The number of megapixels determines the resolution of the images captured with the main camera. A higher megapixel count means that the camera is capable of capturing more details. However, the megapixel count is not the only important element determining the quality of an image.
With a higher light sensitivity (ISO level), the sensor absorbs more light. This can be used to capture moving objects using a fast shutter speed, or to take images in low light without using a flash.
Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
With AF tracking, once you choose the subject and press the shutter release part way down, as the subject moves, the autofocus will follow it. No more out of focus shots.
The maximum resolution available for videos shot with the main camera. Although it may be possible to choose among other frame rates, those recordings usually have lower resolutions.
Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
A phase-detection autofocus system is faster than a contrast detection autofocus system. Even when recording scenes with a lot of fast movements, the videos are sharp and clear.
Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
A timelapse shows a long passage of time sped up. A series of photographs taken from the same position over a long period is joined together to create a short video. It is great way to capture things like the setting sun, or clouds moving across the sky.
Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
Slow-motion is an artistic video effect that makes time seem to go slower. It is achieved by recording a video at a higher frame-rate than the standard playback rate of 24fps or 30fps. Depending on camera capabilities, frame rates for slow-motion videos vary between 60fps and 960fps.
Sony Alpha 7R III + Sony FE 24-70mm f/4 ZA OSS Vario-Tessar T*
Sony Alpha a7 III + Sony FE 28-70mm f/3.5-5.6 OSS
Zoom microphones record high-quality audio and enable you to record sound from a distance. They can be useful for recording meetings, lectures, and presentations.
Battery power, or battery capacity, represents the amount of electrical energy that a battery can store. More battery power can be an indication of longer battery life.
The better the dynamic range the system captures a wider number of values from dark to light leading to more details in low and highlights. Source: DxOMark.