Ever since the tiny Olympus OM-1 35mm film SLR was introduced in the early 1970s (and perhaps even before), there's been a desire among many for smaller and lighter interchangeable-lens cameras. Especially for outdoor photographers, who often must cart gear deep into rugged terrain, the benefit of smaller and lighter camera bodies and camera systems has beckoned strongly.
Today, we have a wide range of very compact digital SLRs in several formats. For those for whom size trumps all, a lot of mirrorless interchangeable-lens cameras are even smaller (though not as well suited to some types of outdoor shooting). Here's a look at what's available to the size-conscious outdoor photographer in today's DSLR market.
Full-frame DSLRs can deliver excellent image quality because their large image sensors can collect more photons and more photons means a higher signal-to-noise ratio. And despite their big sensors, the three compact full-frame DSLRs we're looking at in this article really are compact, about the size of a high-end APS-C model and a bit lighter. This makes them great choices for the outdoor photographer who's after the ultimate image quality in an easy-to-carry package. Their main drawback for outdoor work is for wildlife photography. Full-frame sensors provide a wider angle of view with any given focal length than smaller sensors. The subject will appear bigger in the frame on an APS-C camera and a full-frame one when the same lens is used, and a 24-megapixel APS-C DSLR gives you more "reach" than a 24-megapixel full-frame camera.
Canon's most compact full-frame camera is the EOS 6D, featuring a 20.2-megapixel sensor in a body that measures just 5.7x4.4x2.8 inches and weighs just 24 ounces. It can use all Canon EF and TS-E lenses, but not the EF-S or EF-M optics designed especially for APS-C sensors. EF focal lengths range from a 14mm superwide-angle to an 800mm supertelephoto, plus an 8-15mm fisheye zoom and manual-focus tilt-shift TS-E lenses of 17mm, 24mm, 45mm and 90mm. There are also 1.4X and 2.0X teleconverters, and several true macro lenses, including a 1-5x optic. The EOS 6D's big pentaprism viewfinder shows 97% of the actual image area, while the 3.0-inch, 1040K-dot LCD monitor provides easy live viewing. The camera can shoot full-res images at up to 4.5 fps, and has a normal ISO range of 100-25,600, expandable to 50-102,400. Images are saved on SD, SDHC or SDXC media (UHS-I-compatible). The 6D features enhanced dust and weather resistance, and has built-in WiFi and GPS. It also offers good video capabilities, including 1920x1080 at 30p and 24p and 1280x720 at 60p. Focusing during video shooting is done manually.
Nikon's most compact full-frame DSLR is the D600, which provides a 24.3mm sensor in a body measuring 5.6x4.4x3.2 inches and weighing 26.8 ounces. It can use all AF Nikkor lenses, including DX ones designed for APS-C sensors (the camera will automatically crop to DX format when a DX lens is attached). Available FX (full-frame) focal lengths run from 14mm to 800mm, including a 16mm full-frame fisheye, several 1:1 macro lenses and three manual-focus tilt-shift PC-E lenses (24mm, 45mm and 85mm), as well as 1.4X, 1.7X and 2.0X teleconverters. The D800 can shoot full-res images at up to 5.5 fps, and has a normal ISO range of 100-6400, expandable to 50-25,600. A big pentaprism viewfinder shows 100% of the actual image area, and is complemented by a 3.2-inch, 921K-dot LCD monitor. WiFi and GPS are available via optional accessories. Dual memory-card slots accept SD/SDHC/SDXC media, with UHS-I compliance. The D600 features extensive weather sealing, providing dust and moisture protection equivalent to that of the D800/D800E cameras. Video capabilities include 1920x1080 at 30p and 24p and 1280x720 at 60p. Contrast-based AF is available during video, but is fairly slow.