If you plan to take an image of a rare book or manuscript item, or reproduce an audio or moving image file, it is advisable to do the following:
1) Ask for permission from the repository that holds the items - ask about any specifics, such as no-flash photography
2) Ask for permission to use the image for your own private research or educational purposes:
3) Determine if the item has copyright restrictions or if it is in the public domain. A librarian can give you some guidance on this but ultimately the responsibility for copyright compliance lies with you as the researcher.