Photography needs to be undertaken with care.
Ask permission first when taking closer photographs of people. You will likely find that women wearing a niqab (not just a scarf) are uncomfortable about being photographed. However many more people are happy for you to photograph them although some may ask for a little money. A fee to take photos may be charged inside the pyramids, tombs and museums.
In more and more museums and other places (such as the Egyptian Museum, catacombs in Alexandria and tombs in the Valley of the Kings) photography is not allowed.
Certainly at the pyramids the cameleers will ask for a fee to take photos of them and their camels. Others may not be upfront and only look for money after the photo is taken.
Photos of police or military personnel and installations are forbidden.
Since the Revolution and stories in the press about foreign agents inciting trouble and/or spying, there is a higher level of suspicion of foreigners taking photos so stay aware of what is happening around you.