I didn't even think I messed with the settings, but this video yesterday was not usable...any ideas or settings I should change

You can manually adjust the exposure to make it brighter. Also, setting your ISO to a higher level. The higher the ISO, the more sensitive the camera is to light. If you have too high of an ISO it may cause your footage to become grainy. Also, slow down the shutter speed. The longer the shutter is opened, the more the light gets in causing your photo making it brighter. Play around with the settings and take pictures until you get it to look the way you want.

Try out what jhurst5 suggested and let us know if there was any improvement.

jhurst5 Posted at 2017-1-20 10:35
You can manually adjust the exposure to make it brighter. Also, setting your ISO to a higher level. The higher the ISO, the more sensitive the camera is to light. If you have too high of an ISO it may cause your footage to become grainy. Also, slow down the shutter speed. The longer the shutter is opened, the more the light gets in causing your photo making it brighter. Play around with the settings and take pictures until you get it to look the way you want.

Can you not set both to auto if you just want the AC to do the legwork?

You can also edit the video you have and brighten it up using a video editing software. I use Filmora

Also another thing to do is, while recording video, tap on the dark subject, which will activate the exposure lock and the camera settings will automatically adjust to the best settings to make the object on the exposure lock bright enough. I was flying my drone last night in the sunset, and the drone was focusing the exposure on the sky causing everything else to become dark and silhouetted. All I did was tap on a random dark subject activating the exposure lock causing everything on the ground to become visible and bright.