Ok, so I'm new to backpacking and I'm in the process of buying my gear. After reading through this forum I seem to have broken a rule of thumb in purchasing a backpack: I bought the pack first. So know I'm second guessing my purchase because I bought a fairly large size pack, an Osprey Aether 85. Is this pack going to be too big for my needs? I eventually plan on doing up to a week to ten days backpacking, so I figure a large pack would be ideal. However, as I read more it seams that there are often places to restock on basics. To me this would mean that you would not need to carry as much, thus a large pack is unnecessary. It is still new and returnable, so I’m wondering if I should downsize to the Aether 70 instead. The actual weight variance is only 3oz, so weight is not really an issue, but extra space can cause too much movement, correct? Does anyone own this pack or have some thoughts on my dilemma?

As you've mentioned, you've probably got it backwards to what we'd reccommend to you.

There is probably not a huge difference between the two, however, if it's returnable, and you're not certain of your purchase, one thought might be to return it, go about acquiring some of your other gear, and perhaps try renting or borrowing the first time out.

You might also want to ensure you're thinking about what you want for "normal" backpacking trips, if 10 days out will be "normal" for you, that's great. if not, you may be overbuying and therefore carrying a lot more weight than you otherwise would of most of your trips, just to try to make one backpack do it all. For example, I have a giant backpack, and a big winter tent and sleeping bag. I do most of my backpacking in the summer/fall, and when I do that I am not using my big heavy winter gear. Were I to try to plan for that one backpack and tent to do it all, I'd be carrying a ton more weight on my back for the time I do most of my backpacking.

I would either return the pack and wait until you've accumulated all of your gear to choose the right pack, or I'd keep it and buy a second pack if you find out later on that it's too big.

Check out the "New Pack and New Poster" thread a few lines down on the index - he also bought his pack first. It was an Aether 70.

Buying the pack first is not necessarily a fatal mistake. Buying too large a pack can lead to it riding sloppily, since you won't fill it. However, without knowing what your style and hiking region are, I can't say whether it's too large or not. You might want to take the pack, your other gear, and food and clothing for a "normal" (for you) trip back to the store where you bought it, when they're not busy, and simply ask if you can use floor displays to fill out your gear and put together a complete set of gear you hope to end up using. Load it into the pack, and see if it's too big. If it is, downsize to the Aether 70 or 60. If not, thank the store staff for their time, make at least a small purchase, and vow to continue to patronize them. If you're tempted by a 30% sale online, at least ask if they can meet the price - and maybe buy it at their price, even if they can't. The ability to be able to touch, feel, try, and hear advice from knowledgeable folks really is worth something. But I digress.

If you're sure you want to adopt a minimalist/lightweight style, I think your pack is definitely too large (unless you want to load it up with food and do 2 or 3 weeks without resupply!) If you decide this is the case, go back and replace it with the 70 or 60. However, if you choose the 60, and want to go out for a week or ten days without resupply, you may be committing yourself to choosing other gear that tends more to the lightweight side of the scale: Big Agnes tents, Snow Peak stoves, Western Mountaineering bags, the "Fast and Light" stuff from MSR, etc. You're also probably committing to a more minimalist style: no chair kit, one-pot kitchen, boil-and-soak suppers, etc.

I just recently switched from my much-loved Granite Gear Vapor Trail to an Aether 60 (I found my loads were creeping up above the 20-25 pound level due to carrying more food and water for longer trips into drier areas; the VT suspension just wasn't comfortable enough.) The Aether 60 was just right for a test load of my basic gear (including a down jacket and pants and other winter clothing) and 5 days' food, with room left over. I'm somewhat minimalist, but I also use an air mattress and take a few other small comforts. That total test load, including the 4-pound pack, was still only 31 pounds, including 5 days' food (7 pounds) and 3 liters of water (6 more pounds.)

The 85 may be OK for you, if you have a good idea of what your typical loads will look like; but also consider the 2 smaller versions. Also, remember that the lid compartment is detachable when you're not carrying a filled-up pack.

As usual, I think Phat has nailed an important point here --- can you anticipate what kinds of ways in which you might use the backpack?

In particular, if you suspect you might be inclined at some point to do winter hiking or mountain climbing or scrambling, that pack might be a good choice. Winter imposes a whole lot of constraints that suggest a higher volume pack.

Of course people strive to keep their winter-time base weight low too, but you when you need a better tent, a warmer sleeping bag, more warm clothes and perhaps more backup clothing, you're eating more calories per day ... for me, at least, it's impossible to be in the same ballpark as for a summertime trip.

Get lost, I am the other poser ehem, I mean poster referenced above that bought the Aether 70. I will say, I spent quite a bit of time (3 hours) in the shop (and that wasn't my first trip) talking with the staff and walking around with the pack on my back, loaded with about 30 pounds worth of stuff to check fit and such. My point being, your local shop is a great resource especially if there are avid hikers among them. I hope they took the time to fit you properly with the shoulder straps, belt strap and discuss pros and cons of the different sizes and what they can do for you. I quickly discovered that there isn't a one pack for every situation and I decided on the Aether 70 for 3 reasons:
1. It can be cinched across the back so you can still maintain an ideal pack (from bottom to top instead of just filling the bottom of the pack only) if you don't have enough to fill up the whole pack.

2. There are two day pack options you can attach to the back of the 70 if you need to carry more. This will also serve as a nice option if you are hiking out and back to your base camp in a day.

3. With the 30+ lbs filling up the pack (90% full), it felt like there was no pack at all while I walked around the store...and yes, I felt like a complete idiot, but I am confident the pack I bought is the one I like the best.