This is a comprehensive and easy to understand article about raccoons and how to keep them away from chickens.
I appreciate the mention of them being active in daylight, as I've dealt with a raccoon visit in the middle of the day. It didn't attack any of my birds, thankfully, as I had them closed up in their run. It is definitely a good thing to be aware that their behavior may not always follow the typical pattern.
Great information. I would add, however, that in my experience, flashing lights and noise have done absolutely nothing to deter the nightly visits I get from the racoons. Fortunately, I built my coop like Fort Knox, so the only animal that could get in would be a bear.
In any event, they are worthy of respect, and we all need to be mindful of their craftiness.
Raccoons are one of the toughest chicken predators to deal with. This article has good details about most of the problems they cause, and how to prevent them. Everyone who keeps chickens in raccoon country would do well to read this article, and to follow the advice in it.