The best rule of thumb when it comes to getting a photo release signed is "when in doubt, get a signature." When one or a few individuals are involved and there is time to plan ahead, best practice is to have a photo/recording release form signed.
In the case of a flip video camera or smart phone video recording, have the person state their name and give permission for their video image and voice to be used for educational purposes and/or promotion of ISU Extension and Outreach programs. When capturing events involving crowds, it is nearly impossible to have releases signed. Remember, it's the responsibility of the photographer/videographer to get the release form signed and to maintain a file of those releases with a copy of the image.
Please direct questions to email@example.com or call Steve at (515) 294.2405.