The Denver Broncos issued their final training camp reminder for fans late Thursday night in advance of Friday’s opening day of 2015 training camp, putting just one of the several reminders in big, bold letters:

ANY DETACHABLE LENSES LONGER THAN THE LENGTH OF A CREDIT CARD WILL NOT BE PERMITTED ON CAMP PREMISES.

As the full “Cameras” policy states, “Fans are welcome to use still cameras during Broncos 2015 training camp, but video cameras (and the recording/live streaming of video on other devices such as cell phones and tablets) will not be permitted. Only members of the media will be allowed to bring cameras with professional lenses and tripods to training camp.”

But beyond professional lenses, probably the most-important aspect of the camera policy relates to recorded or streaming video.

In this new era of Periscope, Meerkat, Hang, Streamwire and other streaming apps easily downloadable to most iOS and Android devices, the temptation for fans to broadcast their training camp experience to friends, family and the world wide web at large is immense. So be forewarned that fans who are suspected of live streaming or videotaping training camp practices could face any number of repercussions from the club including and up to removal from the facility.

NFL teams take the sanctity and security of their playbook quite seriously. The media are only allowed to videotape select time periods during practice and there are strict guidelines that must be followed about reporting information such as formations, personnel groupings, trick plays, etc. The same doesn’t necessarily apply to fans – the camera policy is about as far as teams are usually willing to go in controlling their fans’ “view from the stands reporting” – but suffice to say, the Broncos won’t be thrilled if half of the playbook is being live streamed or posted to Vine by overzealous fans.

So as the season kicks off and Denver looks for every edge (legally) possible (ahem, Mr. Brady) to get them back to the Super Bowl, they’re asking fans to do their part and keep the secrets at Dove Valley locked inside those walls.