In reply to AlisonSmiles:
Hi Alison, I've never used a frame bag but I suspect if you need to use one with panniers as well then you're carrying too much stuff.
Bob is spot on, if camping with a proper tent, and maybe a stove, gas, pans etc, then you will probably need panniers, which are fine on a road tour but really cumbersome off road. There is a lot to be said for just getting in a very low gear and slowly spinning your way up long hills while admiring the view.
I did a great trip last year (all on road) with a large 15-20l saddlebag and a handlebar bag, staying in hotels and eating out so only spare clothing, civvies and a camera went with me. Riding the bike just felt like riding a heavier unladen bike. No notable handling issues, it still fet quite nimble.
Bikepacking seems to be the latest big thing, there are masses of blogs and sites about it, so no shortage of info. Let us know how you get on, I'm quite intrigued by the possibilties.