Tripods, Monopods or Drones often leave ghost marks at the bottom of your 360 footage.
Removing tripods can often be tedious, and the simplest way is probably just to cover it up!
Use your logo, or any other image and add it at the bottom in the editor to make your problem disappear. This saves additional work, and is a great way to push in some branding.
However, if you really want to clean up the tripod from your footage completely, here's how you could do that.
Here is a quick tutorial on how to remove the tripod using Adobe Photoshop, Premiere Pro or After Effects:
Mettle Sky Box is now a part of the Adobe Suite (>Adobe CC 2018). You can use the same features from the tutorial using the now inbuilt features of After Effects, like this:
Use the "Immersive Video>VR Converter" effect in place of "Mettle Skybox Converter"
Use "Window>VR Comp Editor" instead of "Skybox Composer"