Another nice landscape feature is an electronic level, or "virtual horizon." This makes it easy to keep the shot level with the horizon even when the horizon isn't in the frame. Viewfinder (and LCD monitor) gridlines can help you align elements when the horizon is in the frame.
Sony's SLT-A99 was the first full-frame DSLR to incorporate a geotagging GPS unit, followed by Canon's EOS 6D. The other current full-frame DSLRs can use an optional geotagging GPS. This unit records the shot's location—latitude, longitude, sometimes elevation and even the direction the camera is pointing—in the EXIF metadata. This means you'll know precisely where each shot was taken and can search for shots by location. You also can plot images on digital maps using this data.
To minimize camera shake and maximize sharpness, you'll want to shoot from a sturdy tripod. But even then, the SLR mirror flipping up out of the light path to make the exposure can cause blurring vibration. Using Live View mode eliminates this problem as the mirror is up all the time in Live View mode (except with Sony's SLT cameras, which use nonmoving semitranslucent mirrors and thus avoid the problem). Many DSLRs have a mirror prelock feature that lets you flip the mirror up after composing and focusing, then wait a few moments for vibrations to settle before making the exposure, but since you can't see through the optical viewfinder when the mirror is up, live view is a better solution with today's DSLRs. It's also a good idea to use a cable release or self-timer delay to trip the shutter, so you don't jiggle the camera as you press the shutter button.
APS-C For Landscape
While prices recently have come down (with new models from Nikon and Canon selling for $2,099), full-frame DSLRs are still pretty costly. DSLRs with smaller sensors—APS-C measures around 23.6x15.6mm vs. 36x24mm for full-frame—cost a lot less and can deliver excellent image quality. In DxOMark.com's sensor ratings for landscape work (dynamic range), the top three cameras are full-frame DSLRs, followed by three APS-C models, then another full-frame, an APS-C, a $40,000 medium-format camera, then seven more APS-C cameras. Granted, there's more to image quality than just dynamic range (the APS-C models aren't far behind the full-frames in DxOMark's color bit-depth ratings, either, lagging noticeably only in high-ISO performance, which isn't a major factor for most landscape work). Current APS-C DSLRs range from 12 to 24 megapixels. Sigma's SD1 Merrill features a unique Foveon X3 image sensor that stacks three pixel layers and doesn't require a sharpness-reducing anti-aliasing filter like most DSLRs, and is a very good landscape camera. Pentax's new K-5 IIs also does away with the anti-aliasing filter.
The biggest drawback of APS-C for landscape work is the smaller sensor's "crop" factor. The smaller sensor, in effect, crops into the full image projected by the lens, narrowing the field of view. Due to this 1.5X "focal-length factor," a 24mm lens on an APS-C camera frames like a 36mm lens on a full-frame model. A few years ago, this was a major problem for digital landscape shooters, who often need wide-angle views. Today, though, there are a number of good wide-angle lenses designed for APS-C (16mm on APS-C provides the same angle of view as 24mm on a full-frame camera, and there are wider lenses available; Canon offers a 10-22mm zoom, Nikon, a 10-24mm zoom, Pentax, a 12-24mm zoom, and Sony, an 11-18mm zoom). Independent lensmakers also offer wide-angle lenses for popular APS-C DSLRs: Sigma (10-20mm zoom), Tamron (10-24mm zoom) and Tokina (11-16mm and 12-24mm zooms). There are also fisheye lenses available for APS-C cameras. So, today, getting wide with an APS-C DSLR is no problem.