01.05 Sony a6400 Video Shooting
The Sony a6400 shoots video in 4k or HD and can save the video files in a variety of frame rates and bit-rates based on the selected video resolution. 4k video is limited to 24 frames per second (fps) or 30 fps, while HD video also has options for 60 fps and up to 120 fps.
XAVC S is a more compressed but acceptable quality sub format of Sony’s high quality XAVC format designed for 4K at high bit-rates. 1 When shooting in 4K or HD it is recommended to use XAVC over AVCHD unless extra file and media storage is needed.
Video File Formats
| Video File Format 2 | Video Output | Frame Rates | Bit-rates |
|---|---|---|---|
| XAVC S 4K | 4K resolution (3840x2160) in the XAVC S format | 24p / 30p | 100 Mbps / 60 Mbps |
| XAVC S HD | HD resolution (1920x1080) in the XAVC S format | 24p / 30p / 60p / 120p | 16 Mbps / 25 Mbps / 50 Mbps / 60 Mbps / 100 Mbps |
| AVCHD | HD resolution (1920x1080) in the lower quality AVCD format | 60i | 24Mbps maximum |
Frame Rates and Shutter Speed
Higher frame rates allow for a smoother illusion of motion than lower frame rates. Basic camera settings for photography include the Aperture, ISO, and Shutter Speed to control the exposure of the image. The same is true for shooting movies or video except that Shutter Speed is liked to the frame rate. A general rule for video is to double the frame rate to determine the Shutter Speed. If an exact double of the frame rate is not available on the camera then the closest Shutter Speed should be chosen.
Shooting still images with a 1/60 shutter speed will create a blurry image if there is any movement in the shot. Unlike still photography, video benefits from this blurriness referred to as motion blur. If every frame of a video is captured sharp then the video playback can seem choppy since it does not mimic the motion blur we experience with our eyes viewing the physical world.
Proper shutter speed selection can also help reduce banding or flickering from electric lights in a scene. Electricity has a frequency of either 60 hertz or 50 hertz depending on where you are in the world. If your camera captures frames out of sync with the cycle of the electricity, it can cause banding or flickering due to the way digital camera sensors, without global shutter, record individual lines of pixels. To avoid banding in your video, set the shutter speed to a multiple of the frequency of the local electricity.
| Frame Rate | x 2 | Shutter Speed |
|---|---|---|
| 24 fps | 48 | 1/50 |
| 30 fps | 60 | 1/60 |
| 60 fps | 120 | 1/125 |
| 120 fps | 240 | 1/250 |
Slow and Quick Motion Video
The a6400 is capable of shoot 120fps video in HD that can be used to create slow motion video effects in video editing software.