We strongly advise you to carry your camera around with you at all times. Tibet is colourful and photogenic and it is certainly worth capturing it on camera. We recommend bringing the necessary photographic film, batteries etc with you. Items such as memory cards in standard sizes are abundant in the major cities and tourist areas.
Not all types of batteries for cameras are available. So take batteries that will last the entire trip. Also bring the correct world plug adapter to charge your camera. It is also difficult to acquire flash lights and other equipment. For printing, you are best to wait until you are back home.
Generally, Tibetans do not mind if you take pictures of them. Always ask permission beforehand, and if people indicate that they are not willing, then respect that. Photos of the Dalai Lama and other materials are illegal. Remember that you put yourself and others in danger if you break these rules. You can make people in Tibet tremendously happy with a Polaroid picture of themselves and will see that suddenly many doors will open to you.
Making photos and videos of government buildings, military facilities, border crossings, airports, police and military officials is prohibited. There should be no photos taken inside most religious buildings, in particular this applies to temples and monasteries in Tibet. If it is allowed then there quite often is a fee charged.