I'm debating this very subject for my own hiking. I have a Canon Tough P&S D20 that hangs from a super magnet on my pack strap that is durable, simple, light and easy while hiking on the trail. But once I arrive at my destination, I would prefer to use a SLR with a wider lens, etc.
There are soooo many angles to this challenge. I've considered small systems. Better P&S cams like G series, S series, etc. Ugh. Expensive, fragile and a whole other system to build and maintain. However, if I were
to buy another system, I think it would be a Pentax K-3
with a WR lens. I've almost bought that several times already and chickened out. It's weather and shock resistant and a very good camera to boot.
I got a Canon SL1 on a super sale before Christmas for $349. I'm thinking it might end being a throw away body if it can't hold up to the hiking. (Shocks, temps, dirt, moisture, etc.) I hate to see that and I don't want to miss out on pictures if the thing dies on day 2 or 3! That's my biggest fear
, not that I lose the $349.
If you do a search, you'll find a thread I started back in November or December on this very subject. I'm still debating. And, I'm still considering spending a small mint on a new ultralight zPacks sleeping bag and tent to save 5+ pounds so I can absorb the extra camera weight without penalty.
Check out http://zpacks.com
for some ultralight gear and you might find a way to make it all work if you can afford the prices. Also look at http://gossamergear.com
for a super lightweight pack. I probably won't go for a UL pack but I am seriously considering the zpacks bag and tent.