It's not very functional to attempt to deny an FDA inspector access to, or techniques for documenting his/her inspection of, your operations and facilities.
However, it can be interesting and useful for you to know the inspector's thinking. Did you ask the inspector his/her purpose for the photographs? It might be that the inspector is documenting something so as to show it to superiors or colleagues in order to decide how to make a judgment call. You might be able to provide additional relevant information that would improve understanding of the situation, leading to an inspection-determination that is more favorable to you.
Some people think that a polite-but-formally-adversarial relationship with an FDA inspector is appropriate, as if they are out to get you if at all possible. I don't agree with that viewpoint. I'd rather be cooperative, open and friendly, just as we are with our NB auditors and visiting customers. Time is money, and my experience is that friendly audits/inspections go faster.