If the flight crew is good, they may let you check the bag in a special hold. You get the bag back as soon as the plane lands, as opposed to waiting at the baggage carousel.
There is usually a "gate check" for this sort of regional jet. This means that you will receive a "bag tag" at the end of the jetway or at the bottom of the stairs to the plane (if you are unlucky and don't get a jetway). The bag then is hand loaded into the hold of the aircraft. I would not count on it going into any "special" part of the hold, and would not do a gate check on any bag that is not strong enough to keep the contents from getting crushed (there may be 8 other bags put on top of it, unfortunately). Roller bags will not fit in the overhead, unless they are really little, and the FA or GA do not see them prior to you boarding (often they are strict and refuse you to even try to take them on). Almost always you will get your bag back in the jetway or on a cart if you get stairs at your destination, however there are a few places where the bag is put on the baggage carousel with the other stuff in the hold (not usually supposed to, so keep your claim stub until you get your bag back, and ask before you give your bag up.)
I suggest you make your carryon look as little as possible, so that you'll be able to take it aboard the aircraft. Mentioning that you have cameras inside will help your case.
Good luck, and have a great trip.