Photography is a gameplay mechanic in Dark Cloud 2 involving the taking of pictures of objects with a camera and turning useful ones into 'ideas'. One can take pictures of various objects as long as it is not something generic like a house, the sky or the ground. Most generic tiny objects do not count either and neither do people. It is also possible to photograph enemies or objects when they're doing something special or unique, like a certain attack or idle movement, these 'ideas' are rare and called 'scoops'. Every new idea counts for one 'photography point', a hundred of which will earn you a new item from Donny. There's a total of 750 possible points to earn, each new idea earns you two points while a scoop is worth five, there's a maximum limit of 294 possible photographs to take.
To make a new 'idea' one needs to take pictures with the camera, which can only hold thirty photographs within the Idea Book. Useless photos will have a plain white border, 'ideas' a faintly glowing one and 'scoops' a glowing golden border. The Idea Book will automatically collect and save the useful photos or delete the useless ones per your request.
One can take three different ideas or scoops to 'invent' a new item with the Idea Book, which creates the know-how of how to produce said item and what items are needed to do so. This is the only way by which one can acquire powerful items earlier, or some items at all, although a lot of items are hinted at (such as the aquarium), the majority of the very valuable high-end items cannot be created this way safe for some Ridepod parts.