You ARE allowed to legally take photos of the abandoned buildings.

You ARE allowed to legally take photos of anything inside either the main museum or museum annex and anything on display outside either of those buildings (as part of the museum display).

You are NOT allowed to take photos of the main entrance and guard station or PMO (with the exception of the welcome sign wall with the letters "CAMP ROBERTS" on it.

You are NOT allowed to take photos of any ACTIVE buildings in use. You'll know which ones they are...they are painted newer and obviously in use compared to the abandoned ones which are dilapidated and falling apart with decay.

Upon leaving the camp, you MUST check in with the MP's back at the PMO to show them your photos. If you bring a film camera, that might be an issue, so I'm assuming you're on your honor with that. I shot all digital and showed them all my photos from both my cameras. They approved all 90 of them.