There are many ways that you can help to save space on your SD storage. This can be helpful if you wish to fit more recordings onto your SD card before having to delete or buy a new one. 

Video Resolution:

• In the settings of the device, you can adjust the Resolution of videos taken. Lower resolution will reduce video files sizes.
• Resolution refers to the number of pixels being used in a video. The more pixels being used, the more data that has to be stored. Lowering resolution will reduce video quality, change based on your needs.