When I go trail bicycling, I sometimes take a small Nikon DSLR with one 18-200 lens. I am trying to find an optimal way to secure the camera to my body as I ride. I travel from 10 to 20 mph and stop when I find an interesting subject. The issues that arise are: a) finding a strap/sling bag combination that I could carry on my back, b) which would be fairly easy to remove, but c) snug enough so that the camera won't bob against my back. In addition, d) I don't want it to wrap around my shoulder or underarms so it makes it difficult to maneuver while biking because e) sometimes I have to make sharp turns or ride over wooden bridges, or jump over the occasional natural speed bump. It's impossible to eyeball the right rig by seeing images or reading descriptions on the internet.. Any suggestions. The easiest solutions I could think of is a small knapsack or forget about the dslr and just carry a smart phone with a good built-in camera, but give up a lot of features.