The differences between the two are very similar to the differences between traditional hard shell luggage and soft shell luggage. Hard shell camera are made from injection molded hard plastic, while soft camera are usually made from high denier nylon. You can also get leather camera, but these are quickly losing favor in response to the versatility, stain resistance and strength of nylon.
Some photographers favor hard shell cases because they’re virtually indestructible. If you’re traveling around the globe and have to check your camera bag, you’ll probably feel better using a hard shell case. If you’re boating down the Nile River and there’s a danger of your camera falling overboard, a good hard shell camera will float, which can save you thousands of dollars. Who wants to see their camera and gear at the bottom of the river?
That being said, most hard shell camera are heavy, cumbersome and can be difficult to pack. There’s usually not much versatility built into the interior, so you’ll have to stick with the default packing method the manufacturer has designed, even if it doesn’t seem practical or intuitive to you. If you want to carry your gear around in a backpack style case, a hard shell camera won’t win points for comfort. It will tend to dig in at the shoulders and isn’t going to conform to the body at all.
Soft shell camera made from high quality nylon, canvas or leather, with nylon being the overwhelming favorite because it’s water resistant but breathable, almost impossible to tear, and comes in a variety of strengths and colors. Far more photographers use soft shell camera cases than hard shell cases.
Soft side camera are easier to pack and extremely versatile. Most have movable dividers that can be rearranged to suit your needs or removed to give you some extra space. They’re also great for traveling with as carry-on luggage. They will conform more easily to the overhead compartment shape without banging up your gear and are easy to stow almost anywhere.
A soft backpack camera will naturally be more comfortable than a hard shell. It will conform to the shape of your back and will have some give to it as you’re moving around. The lightweight material is a bonus when you’ll be hiking long distances with a backpack camera.
The versatility of soft shell camera extends to their interiors. In addition to movable dividers, most will also have mesh pockets for smaller items such as memory cards and microfiber lens cloths. Some soft camera cases are expandable, so you can fill them to capacity when needed, or partially collapse the bag to make it a smaller, more manageable size if you’re only carrying the essentials. Many of today’s soft side camera are also modular – you can order two different cases that work separately, but can be fastened together to make one larger bag when needed.