That canvas camera bag you love looks great with your designer stubble and retro-style Fuji, but heading into the backcountry you’re going to want something a little more up to the task. Hauling an SLR and expensive lenses up the sides of mountains requires a true technical pack. While there are plenty to choose from, including excellent packs from Think Tank, LowePro and Dakine, we decided to take our cue from some of the best adventure sports photographers in the business, guys like Jimmy Chin, Chris Burkard and Dan Patitucci. They all trust their gear to F-Stop packs when they’re skiing the steeps, scouting remote beaches for epic breaks or jugging up a line on a vertical pitch. For the past six months, we’ve been testing two F-Stop bags — the Kenti and the Satori EXP — in conditions as varied as multi-day hikes in New Zealand and peak bagging in New Hampshire.

F-Stop is a relative newcomer to the camera bag scene, and its St. Louis headquarters is incongruous with its focus on packs for mountain sports photography. But don’t let that fool you. Their packs show a design maturity that could only stem from experience and a smart use of user feedback.

The bags we tested represent the opposite ends of F-Stop’s Mountain Series range. The Kenti ($249) is a small technical daypack made for light-and-fast days on foot, bike or skis; the Satori EXP ($379) is their largest pack and is built for multi-day outings.

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Kenti

The Kenti’s defining features are side-zip compartments that allow for access to camera and lenses without removing the pack. Just take the pack off of one shoulder and swing it around in front to unzip the half-moon shaped pocket. The pack comes preconfigured with internal padded compartments inside each side’s zip big enough for a full-sized SLR body with a 200-millimeter attached. We loaded the bag this way for our trip to the Sochi Olympics; the camera with long lens was a tight fit, but it worked. With other lenses attached, it was no problem — and of course there’s plenty of room for shorter lenses, flash units and an extra body, if that’s how you roll.

While most of the Kenti’s interior volume is taken up by the side pockets, there is a small top pouch for lunch and layers and a hidden sleeve inside that can hold a slim laptop. The top-loading section is a roll-top design that provides some expandability and weather resistance. Speaking of the latter, F-Stop packs are made from a DWR-coated ripstop nylon, which proved to shed all but the steadiest downpours. During cats-and-dogs situations we deployed the auxiliary rain cover, but that complicated access to the side pockets. A sleeve pocket on the back of the pack holds small items like lens filters, a notebook, pens and energy bars, though we wished the zipper was a full half-moon for easier access.

In urban use and on trail, the Kenti carries weight well. This is a pack built for fast forward action. The shoulder straps are well padded and highly adjustable with a sternum strap to keep things stable. The thick hip belt is comfortable and sports a small zip pocket for a gel or lens cover. Our only gripe was the lack of torso sizing; one-size-fits-all made it a tad small for our 6’1” height. Also, water carrying options are limited to a small hydration sleeve unless you stow a water bottle in the top compartment.

The Kenti is a perfect pack for the mountain biker, day hiker, climber or skier who needs minimalist performance with full protection for, and access to, camera gear. It also works well for stealthy urban forays, where it looks the part of a common daypack and doesn’t scream “photog” even in the signature electric blue color we tested.

Satori EXP

The 62-liter Satori EXP bears many of the same great features of its smaller brethren — DWR-coated ripstop, hauling prowess and configurability — but carries camera gear in an entirely different, even more versatile way. Rather than integrating the padded compartments into the pack’s body, it makes use of F-Stop’s Internal Camera Unit (ICU) modules for protecting and organizing bodies and lenses. These modules are sold separately and are made to fit snugly into the bottom half of the Satori’s main compartment.

The ICUs are self-contained zippered packing cubes with configurable padded dividers so they can be removed easily for separate carry. This is handy if the Satori needs to be checked through at the airport; you just slide out the ICU, zip it shut and carry your precious camera on the plane using the ICU’s webbed nylon handle. Zipped open and fitted against the Satori’s internal frame, the ICU looks and acts like a built-in camera compartment. The ICUs come in different sizes (small, medium, large and extra large) and shapes (micro, shallow, sloped and pro); we opted for the medium pro, which easily held two bodies and three lenses while still leaving more than half of the main pack body free for other gear. When installed, the ICU is accessed through the half-moon zipped backpad and can be swung around and opened simply by slipping out of the shoulder straps but leaving the hip belt buckled.

Without the ICU installed, the Satori is a bona fide backpacking pack. In fact, this is how we used it for 10 days in New Zealand hiking the famous Milford Track and hoofing it in and out of boats, planes and vans. It carried five days’ worth of backpacking gear easily and supportively. An internal hydration sleeve and mesh side pockets offer water carrying options and MOLLE-compatible webbing on the pack’s side and on the hip belt accept F-Stop or aftermarket accessories. The toggles and loops on the pack’s back are evidence of F-Stop’s commitment to technical sports and can be used for carrying anything from a heavy tripod to trekking poles to an ice axe — all of which we did during our test period. Two top zip pockets and internal mesh organizing pockets will please even the most OCD photographer.

While it is sold as a camera backpack, the Satori’s use of the removable ICU expands its versatility, making it a great travel pack. In fact, it has become our go-to pack for just about every adventure lasting more than a day.