LOWEPRO SPORT 200 AW II.
The simple genius of this pack’s design is noted when with feet on the ground, but not dismounted, you can slide it off your right arm and let it sling down under your left arm to unzip the side camera pocket for an easy grab and click.
This is the best way, bar none other, to carry a DSLR camera on a bike tour. The built in padded camera pocket is large enough for a Rebel 5, or similar camera, with 18-55 mm lens and a 75-300 mm telephoto lens and has all sorts of little nooks and crannies for memory cards, battery charger and cords.
The main compartment is large enough to carry lunch, rain jacket and pants and other accessories. The front pouch expands for a helmet, or when on bike some Reefs for destination sightseeing or the cafe. There is a compartment and slot for a hydration bladder, although the pack does not come with one. The padded waste straps and sternum strap keep this super-lightweight pack secure while riding and there are two easy reach side zip pockets to fit an iPhone 6 with Google bike maps. The back padding is channeled for comfort and breathability. Lastly, there are cinch straps to hold a small tri-pod and tabs to clip a light to. The pack is very water resistant on its own, but also comes with a self-pouched waterproof, hi-viz rain cover.
Note, this pack can also double as a travel pack, but it does not accommodate a laptop; I took it along with my commuter pack as a second personal item on the plane.