There are cams that take photos every few seconds (videos) all day long (day cams) and motion activated cameras that take photos 24/7 via motion and now many that do both. A very cheap yet dependable day cam is the Primos DPS Truth Cam at $65 (Amazon). I am on my 3rd year using mine. The drawback is that beyond 50 yards it is difficult to see a lot of detail but if the rack is half-way big you will see it. Sometimes you will have a hard time seeing if it is a spike buck or not. Batteries (8 AAs) will last about a month in warmer weather, even though you start getting a low battery level after a week or two. Another recent drawback is that now I am having to use an online program to view my pics due to recent Windows updates - it is not a problem for me since I do this in my office anyway. And I am thinking this is because mine might be an older model. This DPS is a day-cam only . I tried an ultra-cheap Walmart special for photos once - it proved to be worth its price and I took it back.

For a fairly cheap camera that takes both photos and videos, the Primos Truth Cam Ultra 35 mentioned by OhioNovice would be a good choice if you did not have a ton to spend. It would probably be my choice for my next camera.