I agree there are two arenas" you either want "shots of record" — snapshots that are a visual record of your trip, or more artistic/commercial quality photographs for publication or sale as artwork.
Having ultralight gear makes life a lot easier for the pro outdoor photographer. In the "old days" you might be hauling something like a Canon F1 with an all-metal body and lenses to match, along with a hefty tripod, film, strobe, etc. I've hauled a 4×5 up a few hills too. And then there was your regular camping gear on top of the load of cameras. I miss those days like a sore tooth.
We're getting some nice compact digital cameras that are close to bridging the divide between point and shoots and high quality SLR's. The waterproof Pentax Optio and Olympus SW series cameras have higher resolution than the best of the digital SLR's offered a few years ago. The waterproof features also take care of the issues with dust getting into your megabucks SLR too.
These issues have been around since George Eastman built the roll film snapshot cameras for people to take snapshots vs the heavy and complicated view cameras. When I went to photography school in the late 1970's, our aged instructors bad-mouthed the 35mm SLR as an amateur format camera. We rolled our eyes.
On the art side, there is that school that uses the simplest type of equipment for a deliberately primitive image, like the Diana and pinhole cameras. The real lesson from these artists is that what you point the camera at is more important than the resolution and sharpness of the image. There are decades of essays and books on these issues. Put the lowest resolution digital camera in the hands of one of these artists and they will find a way to use the limitations of the format to bring back images that provoke and have their own beauty.
Another thing to remember is that images for the computer are limited by our monitors, which are far below the needs for printed images. A 5mp camera will produce images that will still need to be reduced for on-line publication.
What is the real difference between an amateur snapshot and a pro image? The nut behind the viewfinder.
Snapshots are done quickly, at the moment, in process to the actions of the day– a sleepy tent mate, cooking breakfast, a quick grab shot of a viewpoint during a rest stop. A pro will produce snapshots that aren't much different than anyone else, but I would *expect* a higher proportion of well framed, exposed and focused images.
What is different about a pro's best work? Time spent chasing the image. Getting to just the right spot, waiting for the right light, choosing the lens focal length to get the compression and perspective that best interprets the scene. Control over exposure, contrast and plane of focus is also used to aid interpretation of the scene. And the camera will be on a tripod to eliminate motion blur and deliver the best quality image possible.
A pro uses expensive (and heavy) equipment not for its own sake, but to insure that the investment made to get the photographer to the scene produces the best possible images.
In photography school we came to ask this question to illuminate the difference between the photographer and the equipment: would you rather own an image made by Ansel Adams with a pinhole camera, or a rank amateur with the most expensive view camera? Short discussion there.
My best 35mm portraits were made with a old manual Pentax screw mount 35mm camera that cost me $50. It was the setting, the light, the subject, the framing, the exposure, contrast, and my (hopefully) skillful use of the camera. Those were local shots and not made under contract or with a deadline. Had I been sent halfway around the world to take a portrait of some VIP, I would have been duty bound to take good gear just to insure I came back with the goods. Your professional reputation is on the line.
For photojournalists working in extreme conditions, durability is every bit as much the issue as quality of image. If you're dodging bullets or working in sand, dust, water, or extremes of temperature, you need some darn tough gear.
My personal finding is that I take a lot more photos when the gear is with me and easy to use. I reach in my pocket, pull out a tiny camera, flip a switch, zoom and frame and punch the button. I don't need to take my pack off, unwrap an SLR from its protective container of choise, remove the lens cap, worry about the rain/mud/dust, feel obligated to get out the tripod, etc, etc, etc.
