Versatility and portability are important in landscape work because you’ll often need to travel to your subject. The Nikon D810 and Canon EOS 5DS offer high resolution in compact packages. The Pentax K-1 offers features designed for outdoor work, like GPS and star tracking. The Sony a7R II packs the highest resolution into the smallest full-frame body. The Fuji X-T2 and the Olympus O-MD E-M1 II are very popular due to their small size and excellent image quality.
Most landscape photographers carry lenses that cover the range from 16mm-200mm. The Canon EF 16-35mm ƒ/2.8L II is always in my bag, and the Nikon AF-S Nikkor 24-70mm F2.8G ED is also popular. Other popular focal lengths are 70-200mm, 50mm, and 24mm or 28mm wide-angle. If there are two choices in aperture, like ƒ/4 and ƒ/2.8 versions, the wider aperture will be more versatile and give you more low-light work, but will be more expensive. A macro lens and a tilt-shift lens are must-have additions for specialty landscape work.
Don’t waste your investment in a good camera and lenses by buying a flimsy tripod. You don’t want a tripod that’s so heavy you leave it behind either. Ideally, your tripod should extend taller than your head and should also lie flat on the ground, so avoid center posts or choose a model with a removable center post. I like Gitzo carbon-fiber legs because they’re light, stiff and durable, but there are numerous great brands. I like to spend the extra money for carbon because the material is super-stiff and lightweight. Carbon legs are also not as cold as metal ones when temperatures drop. Simple, flat quick-release plates are guaranteed to twist, so the best solution, which is admittedly expensive, is an L-bracket custom fitted to your camera body from Really Right Stuff or Kirk Enterprises. The dovetail on the L-bracket fits the Arca-Swiss-compatible clamp on tripod heads available from Really Right Stuff, Acratech, Kirk Enterprises, Arca-Swiss, Oben, Benro and Induro.
I like Lowepro’s Toploader Pro 75 AW II bag, worn as a chest pack, because it lets me keep a body and two lenses handy when hiking, but there are countless great bags. Landscape photographers will want to focus primarily on backpack-style bags, especially those from Tamrac, Think Tank, Lowepro, Manfrotto and others.
I carry polarizing filters, which I use sparingly, primarily with my 70-200mm. If I anticipate shooting waterfalls, I carry 2-, 3-, and 4-stop solid neutral-density filters. I’ve retired my graduated neutral-density filter kit in favor of digital methods of combining two different exposures of the same scene.