Might be a good time to test the SD880.

It's a conundrum, I feel your pain 

As I look back through the pictures I have taken on backpacking trips I've found that wide angle landscape shots outnumber telephoto shots about 15 to 1.  I also do the majority (well pretty much all) of my shooting in the morning and evening in lighting that is less than perfect for tele lenses that aren't supper fast.

I think you would regret toting the 70-200 along since it's so heavy but would greatly appreciate having the 16mm, but I guess it mostly depends on what you like to shoot outdoors.

A tripod is the other heavy thing to have to lug around.

One thing about spotting animals is that by the time you stop and change into that long lens the animal may very likely be gone and then you will find that a 200 is not even long enough.  Unless you are hiking with other Canon users of course and can share lenses and the burden of carrying them?  I know how heavy my 70-200 is - for a afternoon I'd take it, but a whole week plus your gear and food...  Of course if you run into Sasquatch while you are out there you will never forgive my advice. 

I recently returned from shooting in the Sierras. I had a 14mm fisheye, the 28-70 2.8 and my 28-300 Canon L glass lens with me. The weight was hard BUT there were shots I would have missed had I not brought those exact lenses. I guess ask yourself how mad you would be if you missed a certain opportunity because you wanted to lighten your pack Have fun!!

if i brought a long lens it would probably be the 100-400 L

I normally travel with the 24-70L and the 100-400IS. Whenever I analyse the results of the trip however the 24-70 will be responsible for 95%+ of the resulting stock. I'm usually travelling via motorhome though so weight is not an issue. If I was on a week's walk I'd probably just take my 135 f2 and hope to be able to crop telephoto shots later if necessary. You could also take one of your extenders.

first, re sherpas - on my Nepal & peru treks i carried mre lenese, tripod, etc, but you still have the question of what to carry during the day, since the porters are usually not available

i like to g w one lens since it prevents dust, etc in harsh environments - i have an 18-200 for my dslr. 

however, i've been amazed at the results from my new sony hx1 with 20x zoom, and may start carrying that instead.  it's also an incredible camera for low light [it takes 6 images, then averages them t get the sharpest image]

i normally walk with a monopod; i'll add a tripod if somene else is carrying weight, for evening & early morning camp & sunset scenes;  for a week long backpack, i sometimes toss in a tabletop tripod, or just use a stuffsack filled w clothes

the best advice i'd have is to carry the camera ready to shoot -- if it's back in your main pack, all too often you'll be too tired get it out and miss great shots.  i did this even when mountain climbing

s

TONS of great advice going on here!! 
    Kinda boils down to 1.  where you're backpacking, how long, and what you'll be seeing... and as some alluded to... altitude. You can carry a heck of a lot more at 6k than you can at 10 and up.. LOL
     I am really comfortable with my 35-128.... it gives me plenty of range on the trail in the woods/brush, can pick up decent close ups, nice capture through the 'prime' shots and a minimum of long glass. I've too found that caring really long glass (300 & up) usually didn't give me results that I was happy with... for one, the 'animal ran away syndrome'  and... more than not, I dont carry a tripod when backpacking/bushwhacking and there may not be a helping tree or rock around, hence the shot was never clear as I wanted.
   Never had a sherpa, so... on long days/overnight or thru hiking, weight is always an issue. Sorry to say, but food and a good sleeping bag/pad far outweigh photography issues... (at 60 I'm getting too old to sleep on cold rocky ground ha ha ha - paid my dues..)
    If youre going to have superb wide open landscapes on the trip... any good wide angle is a must. 
    And of course as we all sometimes forget.....  dont forget backup power and memory.  Even after all these years.... just a couple weeks ago, I did a day hike out to a location...  busted my hump getting there..... wipped out the cam to take my first shot.............    NO FLASH CARD.   At least I got to sit there, eat a nice lunch and enjoy the views..... just couldn't bring any views home.. LOL
     One other point on the 'where'  you'll be...  Doing snow,  or  especially desert... I really do shy away from changing out glass any more. I try to make the 28-135 work for me.

 Where you headed to anyway, Leaf?    =tom

I just got back from a week at a camp and had the fortune to be fishing near the shore when a Bald Eagle flew over and perched on a nearby branch of a dead tree.

i have a 55- 200 sigma and was crying like a little baby because i didn't have anything more powerful - to really capture it in any quality better then a snap.  Physically moving closer wasn't an option as I have yet to learn how to walk on water.

I also spent hours investigating the world through the macro lens - tiny insy bitsy bugs crawling on moss and slugs on shrooms - and rare plants - gotta love the microcosm I have a small tripod about 8 inches it turned out to be invaluable for this - Im going to pick up one a bit bigger maybe a foot or so in length - small enough to get down in the leaves but not so tiny it has issues peeking over a fallen branch in front of the subject lol

I got caught in a deluge downpour - a real soaker but wanted to continue taking pictures and wished i had brought some sort of plastic cover i could flop over me and the camera to protect from rain but still continue shooting.  someone suggested getting one or two of those clear plastic  emergency rain coats that fit in your pocket.

just some ideas that are still fresh in my head from my trip

best of luck on the trip

My favorite travel/hiking lens is the 24-105mm, compared to the 24-70 its light weight and doesn't extend out as far with the lens hood on.  It also has the longer reach... its a f/4, but I don't need 2.8 if I'm outside.

I'm going to Yellowstone in a couple of weeks and will bring the 100-400mm, but that's only because I know I'll see wildlife, otherwise a 70-200mm is fine and It probably won't be used much anyway.

Also, I don't leave home without the Gorilla Pods for SLR's, wrap that thing around stuff and balance it on the ground.  Have used that on every trip.

This is exactly why I have Olympus. E-410 weights nothing, however with pro grade lenses its abit too small to provide proper handling. Despite that Im using it. Two lenses Zuiko 14-54/2,8-3,5 + 50-200/2,8-3,5 provide me with excellent maximum aperture, superb optical quality and cover 28-400 eq. FF. Zuiko 14-54 is able to focus 18cm from sensor (thats just few cm from front lens). This setup together weights not even 2kg including filters (CPL, IR, ND4). If I need I can swap heavy 50-200 for extra small and light 40-150/3,5-4,0 (results from my personal extensive testing show that this * cheap lens delivers nearly same results as 50-200, but you must sacrifice maximum aperture and 100mm eq. on the long end).
14-54 + 50-200 are both one of the most weather/dust resitant lenses ever and their weight/price/optics ratio is something unseen with any other manufacturer. Together with sealed E-3 body they do provide killer outdoor setup with acceptable weight and excellent results up to iso800 (over 800 Olympus suffers from higher noise because of smaller sensor).

I do not have UW lens, I would like one, but unfortunately have no budget and if I need, I still can stitch photos together in PC.

If I desperately need to save the weight, then I would go E-410 (or newer 420 or 620) + 14-45/3,5-5,6 + 40-150/3,5-4,0 (not even a one kilogram!) or add ZD 9-18 + ZD 70-300 totaling in less then 2kg and covering unbeliavable 18-600mm eq. with still pretty acceptable optics.

http://www.redbubble.com/people/cascoly/art/everything/tags/autumn

has some shots from banff and glacier, among other NPs -- when you're ready to go, i'd be happy to suggest some places t visit

steve

Perfect timing!  Yesterday I found an article that might help you, Leaf.  Although the information is regarding Burning Man, which is a huge week-long counterculture community art festival in the middle of the Nevada desert with very extreme conditions, it should provide some useful information for your trip.  I'm leaving Saturday for 10 days of alkaline dust, wind and heat...can't freakin' wait!!!!!

http://www.burningman.com/press/photo_guide.html