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Reviews > Packs > Internal and External Framed Backpacks > Osprey Atmos 65 > Test Report by Greg McDonald


INITIAL REPORT - May 08, 2009
FIELD REPORT - August 04, 2009
LONG TERM REPORT - October 01, 2009


NAME: Greg McDonald
EMAIL: gdm320 AT yahoo DOT com
AGE: 22
LOCATION: Boynton Beach, Florida
HEIGHT: 6' 0" (1.83 m)
WEIGHT: 225 lb (102.00 kg)

I have been camping for 17 years, 12 of them have been spent hiking in the backcountry. My hikes are almost exclusively in Florida and generally range between one and three nights. My all-time favorite hike was a 10 day expedition in the Philmont Scout Ranch in Cimarron, New Mexico. I consider myself a lightweight but comfortably equipped hiker, with a pack averaging between 25 and 30 lb (11 and 14 kg).

Osprey Packs


Product Information & Specifications

Osprey Atmos 65
Image courtesy of Osprey
Manufacturer: Osprey
Model: Atmos 65
MSRP: Not Listed
Initial Size Received: Large
Listed Capacity: 68L (4200 cu in)
Listed Weight: 3 lb 12 oz (1.7 kg)
Measured Weight: 3 lb 12.7 oz (1.72 kg)
Listed Dimensions: 30 x 14 x 12 in (77 x 36 x 30 cm)
Initial Color Received: Green Apple (Also available in Graphite Grey and Aspen Gold)

Product Design and Features

The Atmos 65 is a lightweight pack from Osprey's "Ventilated Backpacking" series. The basic design of the pack is pretty standard: a top-loading pack with a floating lid and a sleeping bag stuff compartment in the bottom. From this angle, it isn't all that different from the first internal frame pack I ever used about 10 years ago. Something that I've noticed over the years is that more often than not basic designs stay the same - the difference is in the details.

The details are where I find myself intrigued by the Atmos. The Osprey website mentions several of the Atmos' features including dual vertical front zippered pockets, InsideOut compression straps, Osprey's Stow-on-the-Go trekking pole attachment system, tool attachment loops, a removable floating lid, a waffle-foam harness, and dual hipbelt pockets. Aside from these things that Osprey has listed I've also found that the Atmos is hydration-system compatible with a sleeve for the bladder and outlet for the hose and has an emergency whistle integrated with the sternum strap. The photo below shows a number of the Atmos' features and design elements. The BioStretch mesh backpanel, Stow-on-the-Go attachment, waffle-foam shoulder straps, and the sternum strap system are all visible.

Atmos Features

A big detail of the Atmos is the suspension system. The Atmos utilizes Osprey's AirSpeed suspension. Basically, AirSpeed uses a curved backpanel on the pack's body with a tensioned mesh "trampoline" style backpanel. This creates a space between the pack body and the backpanel which allows for airflow across my back. I've used a similar system, Gregory's JetStream suspension, with excellent results in warm weather and I am very excited about the prospect of testing Osprey's take on the design. The image below probably explains the design far better than I ever could.

The blue squiggles are cold air.

The primary concern that I have with designs like this is that the curved backpanel shifts the weight further from my body, therefore changing my center of gravity. Theoretically this could cause me problems by throwing off my balance while moving and scrambling, so I will be paying close attention to the shifting of my pack load. On the topic of a shifting pack load, I am a bit concerned and was initially a bit baffled by the fact that the Atmos does not have a lumbar pad. On most packs I have used in the past, the lumbar pad has been crucial for transferring the load from my back to my hips and also maintaining stability.

The Atmos seems plenty large to serve as a multi-day pack. The majority of my trips are simple overnighters, but I also have a handful of two and three night trips in store for the Atmos. During my test packing, I had no problem getting all my usual gear into the main compartment of the pack. As I mentioned before, the Atmos is a top loader so I have to pack and unpack everything through the top opening. There is no front or side access to the main compartment because Osprey instead opted to put two vertical zippered pockets on the front for items that might need quicker access. I packed things like my rain gear, pack cover, food, water filter, and other miscellaneous but important items in there so I can get to them easily.

I'm also a fan of the divider in the bottom of the pack and separate access to the sleeping bag compartment. This was a feature that I had on my first internal frame pack that I lost with my most recently used pack that I truly missed. While exploring the pack I was able to get both my Big Agnes Lost Ranger into the compartment without a problem and more than easily fit my Mountain Hardwear Ultralamina 45, so there is plenty of room for both of my bags.

The floating lid up top is deceptively large on storage space as well. The stretch pocket on the front of the pack (between the two vertical zippered pockets) stows a fleece well, which I like because it should keep it nice and handy so I can slip it on and off as temperatures vary. The only pockets I wasn't too thrilled with are the hipbelt pockets, which weren't quite as big as I had hoped for. Still, I was able to comfortably store my GPS on one side and my compass, knife, and small flashlight on the other.

One feature that I've started to look at very carefully recently is compression straps that can be routed both inside and outside the stretch water bottle pockets on the side of a pack. Osprey calls their system "InsideOut" compression straps. The straps are easy to route and re-route as necessary, and the stretch-woven pockets are the perfect size for my 1L Nalgenes that I pretty much always carry.

Fit and Comfort

I must admit that I made an error when ordering this pack that has affected my ability to report on the fit and comfort of the Atmos at this stage. I'm a bit of a sizing anomaly when it comes to packs, in that I tend to need a size medium in terms of torso length but a large in terms of harness and hipbelt size. Because I am a bit close to Osprey's maximum threshold for size medium on torso length, I opted for a size large for this test. Unfortunately, this turned out to be an error in judgment and I will need to request an exchange to move me down to a size medium.

After loading the pack up with about 25 lb (11 kg) of weight, I noticed the shoulder straps were putting pressure on the sides of my neck causing a fair bit of discomfort. I'm thinking that this is a problem caused by the angle of the shoulder straps. Because of the longer torso length, the shoulder straps attach to the pack pretty high up on my back and do not appear to be allowing the straps to take the proper angle over my shoulders. When I allow the pack to ride lower on my back to simulate a shorter torso length, I noticed an improvement. At this point I'm not so much concerned with a design issue, I'm operating under the assumption this is a sizing problem.

Since the fit of the pack is wrong for me, it is difficult for me to confidently comment on the overall comfort of the pack at this point. What I can say is that the harness itself feels good by itself. The foam is soft but still dense enough to offer sufficient padding. The hip belt, even without a lumbar pad, is quite comfortable and transfers the weight well to my hips. With the test weights I also did not notice being thrown off balance even though the curved backpanel moves the weight further away from my center of gravity.

One positive thing that happened while I was exploring possible solutions to my fit problem was that I discovered how easy it is to make adjustments to the Atmos. There aren't a whole lot of adjustments that can be made since the frame is pretty much fixed the way that it is, but all the harness straps, sternum straps, load lifters, and other minor adjustments are very easy to operate even with the pack on and loaded with weight. The only minor annoyance is that the load lifters sometimes get hung up under the floating lid if the Atmos is not packed up very much.

Down the Trail

The Atmos seems to be a very nice pack that is loaded with lots of cool and useful features. I'm excited about the prospect of getting the pack into the field and seeing how she handles... right after I get it exchanged and get the sizing all sorted out. Fortunately, my Field Report should feature a good look at Osprey's Customer Service as I'll get to see how they respond to my issues.

So far the thing I find myself liking the most is the AirSpeed suspension, but I have to say I'm impressed by all the little details that Osprey has included with the pack and am anxious to see whether or not they will make a difference for me in the field. My only disappointment at this point is my fit problem.

This concludes my Initial Report on the Osprey Atmos 65. Please check back in early July for my Field Report where I am confident I will have tons of new information to share. I'd like to thank Osprey and for the opportunity to test the Atmos 65!


Testing Conditions and Locations

The first two months of my testing were a little different from my usual stomping grounds in Florida. My summer travels brought me up into Massachusetts and Maine which provided me a bit of relief from the oppressive Florida heat and a new testing opportunity for the Atmos. The Atmos hauled my gear on a two-night trip in Southern Maine around Folly Pond in addition to a short overnighter on the Florida Trail.

Elevations have ranged between sea level and 285 ft (0 m - 87 m), temperatures in Maine ranged from 52 F during the night up to around 75 F during the day (11 C - 24 C) with temperatures in Florida starting at 75 F and rose to nearly 95 F (24 C - 35 C), and I encountered precipitation on two of the occasions.

Field Observations and Performance

At this point I have mixed feelings about the Atmos that are pulling me in different directions when it comes to forming an opinion on the pack. On one hand, I really like the features and most of the design elements that the Atmos offers. On the other hand, there are one or two design issues that are effecting the fit and physical comfort of the pack.

As I mentioned in my Initial Report, I immediately noticed a precarious sizing issue with the large size. The issue that I had originally was resolved by moving down in pack size. My problem at this point must revolve around my torso length and specific proportions and measurements. I feel like the medium is a little bit short for my torso length while the large was considerably too large. It's almost as if I'm stuck in a no-man's land of sorts regarding the sizing. What I know from the exchange is that, for me, the medium is a better fit in terms of torso length than the Large but it is still not entirely perfect.

The other issue that arose after I swapped to a medium is the length of the shoulder straps and the hip belt. I don't have any of the straps maxed out, but I'm pretty close on the shoulders and hips. Normally having a medium torso but needing a large harness size (for the shoulders and hips) isn't a problem with Osprey, unfortunately the Atmos is one of the models with a fixed harness that cannot be swapped out. The pack fits fine with the medium harness, but I'd certainly prefer it if it were the larger size to give me some additional adjustment room.

Pull Loop

Sizing issues aside, I'm reasonably pleased with the rest of what the Atmos has to offer. Osprey certainly didn't skimp on the features on the Atmos. There are quite a few little details that have been useful for me. One of the smaller details, but one that I really like, are the large hoop zipper pulls on the vertical pockets and the sleeping bag compartment. The Stow-on-the-Go trekking pole attachment has also been nice handy for the times I need to get my poles stored quickly so I can be hands free but then be able to get them back in-hand without having to stop and take my pack off. I have also been using the external tool loop to strap on a small camp stool.

Problem SpotThe suspension and I, just like the sizing, have a bit of a love-hate relationship. When I've had my pack weight under 30 lb (13.6 kg), even for long hours and high miles, I've really liked it. At these lighter weights the AirSpeed suspension with the curved frame and mesh backpanel have really been a blessing in warmer weather. Ventilation across my back has been very good overall. Additionally, the waffle pattern hip belt and shoulder straps seem to me to have a positive experience in terms of ventilation and moving fresh air across these normally restricted areas.

Problems with the suspension for me do not start to arise until I creep up above 35 lb (15.9 kg) or so. At this point I start to feel additional stress in my shoulders combined with awkward pressure on my hips. In my opinion, the issue for me here is the lack of a lumbar pad in the design. At certain angles and under certain conditions part of the suspension starts to push directly on my hips which can be very uncomfortable. The photo to the left is the problem "area" of the suspension that starts riding on me. I suppose that getting up over 35 lb (15.9 kg) is really climbing away from the purpose of an "lightweight" suspension, but it's still worth mentioning.

Regardless of the weight I've been hauling, one thing I haven't had any issues with is being off-balance. I have had no problems adjusting to the shift in my center of gravity due to the curved backpanel, which was one of my original concerns.

Down the Trail

The Atmos 65 is a mixed bag of features that I really love weighed against one or two design issues that are effecting the fit and physical comfort of the pack. I really feel like I need to spend more time in the pack before I can start to draw any real conclusions about the Atmos. I must say that I feel like the features and overall design are very well thought out and executed. For lack of a better term I think I'd call it "user friendly". However, even this early on I know there are two things I'd really like to see changed. I'd like to see the addition of a lumbar pad to improve the fit up against my back and prevent rubbing on the pack body under heavier loads and more adjustment to the suspension of the pack itself so I could customize it to fit my unique shape a little better.


Testing Locations and Conditions

Over the final two months of the test series the Atmos has seen three overnight trips totalling four nights in the field as well as one day used as a picnic-hauler for the family. My overnight trips have been in the Ocala National Forest, Myakka River State Park, and the Florida Trail between Lake Okeechobee and the Atlantic Ocean.

Temperatures have been pretty brutal, ranging between 85 and 95F (29.4 and 35 C) with humidity creeping up towards 90% on one occasion. Humidity was particularly high on my most recent two-night trip where I encountered nearly 2 in (5 cm) of rain. In total, I encountered at least some amount of precipitation on all three of my overnight trips.

Field Observations and Assessment

The Atmos and I continued our love-hate relationship over the final few trips of the test series. I mentioned in my Field Report that discomfort with the suspension started at around 35 lb (15.9 kg) for me, but after my last trip I think I'd like to amend my statement to indicate the problems really start in the 30 - 32 lb range (13.6 - 14.5 kg). I narrowed down the "maximum comfort" range to about 28 lb (12.7 kg) for me. Once I start to carry loads any heavier than that I begin to notice the previously-mentioned rubbing of the pack frame against my body which flat out does not work for me.

The pack is easily large enough in terms of volume to hold several days worth of solo gear. During one of my multi-night Field Report trips, as an example, I carried nearly all the gear for both my fiancee and myself with space to spare but the weight exceeded my personal comfort range. This creates a bit of a catch-22 where I have the space for lots of gear but the suspension doesn't really support it.

I also previously mentioned a problem with the medium harness concerning the size of the hip belt and length of the shoulder straps. Long-term this hasn't proven to be any sort of issue, I just have to hope I don't squirt up in height at all before I'm done growing and I need to try to avoid the extra serving of stuffing at Thanksgiving Dinner. I certainly do wish that I'd had the option to go with the larger size hipbelt and shoulder straps though.

One thing that I really can't praise enough is the ventilation that the Atmos offers. In a word I would describe the ventilation as fantastic. The most miserable time of a hot day for me is when the air seems to go stagnant and it just gets sticky hot. These are the times when I appreciated the air flowing across my back more than ever. The AirSpeed design truly made these times more bearable. In my opinion it is the Atmos' most outstanding feature.

On the topic of features, I'm happy with almost all of them. I'm not going to re-hash the feature list, but I want to give honorable mentions to the integrated hydration pocket and tube port as well as the hipbelt pockets (though I wish they were a bit larger). The only feature that I found to be excessive and not particularly useful are the compression straps on the sleeping bag compartment because I never really had a need for them. When I've packed either of my warmer weather sleeping bags into the compartment I haven't needed to compress the compartment any further. The up-side, the straps themselves are removable so I've just taken them off for most of my trips to keep them out of the way from snagging and shaved an ounce or two.

I haven't had any issues to date with durability. The Atmos certainly isn't a bushwhacking pack so I haven't used it at all for that purpose and we have stuck to reasonably well maintained trails. I try not to abuse my gear on the trail so I haven't been trying to beat the stuffing out of it, but it's seen its share of normal rough and tumble. The buckles are still in good shape, I haven't found any unusual or excessive fraying of any of the straps, and the pack body is still pretty clean. I've washed the pack once by taking it outside and giving it a good blast with the garden hose which took care of most of the dirt and grime. Overall, I'd say the Atmos is aging pretty gracefully.

Final Thoughts

My overall opinion of the Atmos remains pretty much unchanged from my original thoughts. On one hand the Atmos has a lot of features that I find very useful and really enjoy. On the other hand, however, I have some sizing problems and a relatively low top-end maximum weight capacity that cause me some pretty serious comfort issues.

In the end, these negatives will probably prevent me from using the Atmos extensively in the future except on very lightweight trips so I can avoid my discomfort with the suspension rubbing. Additionally I expect the Atmos will still see some use in hot weather where the excellent ventilation becomes an important factor.

This concludes my Test Series on the Atmos 65. I'd like to take one final opportunity to thank the both Osprey and for the opportunity to participate in this test.

This report was created with the Report Writer Version 1.5 Copyright 2009. All rights reserved.

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