I used to ride a lot, and did a bunch of photography. Carried my camera in a bag that mounted on a little rack on the handle bars. Bag slipped right off when needed, full zippered top, contents very accessible. And it's like 9" from your hands. Don't know why something like that wouldn't work. Very handy.
Google handlebar bag. You should get several thousand hits. Cannondale markets a bag that is nice and small but large enough to carry what you need. Velcro straps keep it on and are easy to remove if you go in a store or something like that.