Canon XA40 4k Video
Information on Disk Space Size
When it comes to video, capturing the best quality footage is always a top priority. And while shooting in 4k may seem like overkill for some situations, it can be well worth it in the end.
On cameras like the Canon XA40, shooting an hour of 4k video takes up about 70GB of space on your SD card. This means that if you plan on filming for an hour, you should have at least a 128GB card in the camera slot. The amount of disk space required can vary depending on how many audio channels are being used. For example, if you're using two microphones instead of one, then your disk space requirements will go up by 50%.
If you have a 64GB card and are only using one microphone with 4k resolution and 30fps (frames per second), then you'll max out at around 55 minutes of footage before needing to switch cards or start deleting files.