Digital cameras with full-frame sensors can provide better image quality than digital cameras with smaller sensors, and that’s their main attraction. Larger sensors also have room for more pixels of any given size, and more pixels mean the ability to reproduce finer detail in images. Larger sensors can also deliver narrower depth of field— important for selective-focus work and portraiture, and for “cinematic” video.
The downside is that full-frame cameras tend to be bulkier than cameras with smaller sensors, as well as more costly, but these drawbacks have diminished greatly in recent years. We now have three full-frame, all-in-one compact cameras, and where the first commercially successful full-frame DSLR cost $7,999 when it came out in 2002, today even the high-end Leica full-frame digital cameras sell for less than that. In fact, right now there are seven full-frame cameras selling for under $2,000.
The term “full frame” comes from the fact that these image sensors are the size of a full 35mm film image frame: 36x24mm. There are digital cameras with smaller sensors (APS-C, Micro Four Thirds, “one-inch” and even smaller), and there are digital cameras with larger sensors (“medium format,” with sensors from 44x33mm to 53.9x40.4mm). Due to its greater surface area, a larger sensor can collect more photons with a given exposure (exposure essentially being a measure of photons per square millimeter, and larger sensors have more square millimeters). More photons mean less photonic noise, and a better signal-to-noise ratio—less image noise.
Sensor size also affects a given lens focal length’s field of view. A smaller sensor crops into the image produced by the lens, narrowing the field of view (see illustration). Camera manufacturers generally list a focal-length factor in their specs, which lets you know how much field-of-view narrowing you’ll get compared to the same focal length used on a full-frame camera.
Note that the actual focal length does not change when you change the sensor size; a 50mm lens is 50mm no matter what camera you use with it. However, when used with a smaller APS-C sensor (1.5X focal-length factor), a 50mm lens will deliver a field of view equivalent to that of a 75mm lens on a full-frame camera. And a 50mm lens delivers a field-of-view equivalent to that of a 100mm lens on a full-frame camera if you use it on a Micro Four Thirds camera (2X focal-length factor).
Consider a 35mm lens. On a full-frame camera, it’s a wide-angle. On an APS-C camera, it produces the field of view of a 52.5mm lens on a full-frame camera, considered a standard field of view. And on a Micro Four Thirds camera, a 35mm lens produces the field of view equivalent to a 70mm lens on a full-frame camera—actually, a short telephoto! This is why some wildlife and sports photographers prefer APS-C to full frame; assuming equal pixel counts, APS-C provides 50% more “reach” with a given focal length, especially advantageous for extreme telephoto work.
Then there’s depth of field. A 35mm f/2.8 lens used on a Micro Four Thirds camera produces the field of view of a 70mm lens on a full-frame camera, and the depth of field of an f/5.6 lens—not the depth of field of an f/2.8 lens. That’s because the 35mm lens at f/2.8 and the 70mm lens at f/5.6 have the same aperture diameter: 12.5mm. To get the same narrow depth of field and angle of view a 70mm f/2.8 lens can deliver on a full-frame camera, you’d need a 35mm f/1.4 lens on the MFT camera.
To get the same image with an MFT camera as a full-frame camera produces (in terms of framing, subject size, perspective, depth of field and photonic noise), using an MFT camera, you’d need a lens of half the focal length and half the maximum aperture used for the full-frame photo.
Today, we have 10 full-frame DSLRs (plus some of their predecessors still available new), a full-frame DSLT, three full-frame mirrorless models (plus two superseded mirrorless models still available new), three fixed-lens, full-frame models, three Leica full-frame rangefinder digital cameras, and three full-frame specialty cameras. Each can shine in at least some aspects of outdoor photography—high-megapixel landscapes, quick wildlife and sports action, low-light work (including one camera designed for astrophotography)—even some compact, take-anywhere models.
Canon EOS 5DS R
Canon produced the first market-successful full-frame DSLR, the 11.1-megapixel EOS-1DS, back in 2002. Today, the company offers five full-frame models. The flagship pro EOS-1D X features an 18.2 MP Canon CMOS sensor, 12 fps shooting with AF for each frame (14 fps for JPEGs), extremely rugged construction, and excellent high-ISO performance. It’s very popular with budget-blessed bird and wildlife photographers, as well as sports-action shooters.
Canon’s newest full-frame DSLRs are also the highest-pixel-count 35mm DSLRs from any manufacturer, the 50.6 MP EOS 5DS and EOS 5DS R. They’re identical except the low-pass (AA) filter function has been canceled on the R model, offering even more sharpness at a cost of possible moiré and artifacts with subjects containing fine patterns. The 5DS models should be popular with landscape specialists, allowing for huge prints with lots of fine detail. An advanced mirror mechanism and user-selectable shutter-release lag help suppress camera vibrations, while 1.3X and 1.6X crop modes are handy when you don’t need huge 50 MP files. List prices are $3,899 (5DS R) and $3,699 (5DS).
Rounding out the Canon full-frame line are the EOS 5D Mark III, a 22.3 MP model with highly regarded video features and a street price of $2,499, and the EOS 6D, the entry-level full-frame model with a 20.2 MP sensor and a street price of around $1,699.
Leica’s classic M-series 35mm rangefinder models are longtime favorites of well-heeled street photographers and those who like the simplicity and speed of rangefinder focusing. Today, Leica still offers 35mm cameras, but also several full-frame digital rangefinder M-series models, as well as a new full-frame model with a built-in lens. The flagship M digital model is the M-P, which features 24 MP Leica CMOS sensor, 3 fps shooting, classic rangefinder focusing, plus live view with focus peaking on the 3-inch LCD monitor. It can also do 1080/24p video, with a list price of $7,950. The “economy” M model is the M-E, with an 18 MP CCD sensor, and no video or live view, and a street price of around $4,800.
Leica also offers two M Monochrom models. These have no RGB filter grid over the pixels, and thus no demosaicing is needed, resulting in noticeably sharper images. For photographers specializing in black-and-white, these are great tools (but, remember, they don’t shoot color images).
The newest (and lowest-priced) Leica full-frame digital camera is the compact Q, with a 24 MP CMOS sensor, built-in Leica Summilux 28mm f/1.7 lens, a high-resolution EVF, plus a 3-inch touchscreen monitor, contrast-based AF and 1080/60 video. Street price is $4,250.
Nikon’s first full-frame DSLR was the 12.1 MP D3, introduced in 2007. Today’s Nikon full-frame lineup is led by the flagship pro D4S, with a 16.2 MP CMOS sensor, 11 fps shooting with AF for each frame, very rugged construction and excellent high-ISO capability. The D4S is popular with bird and wildlife photographers, as well as sports-action specialists.
The D810 features a 36.3 MP CMOS sensor with no OLPF for maximum detail, and excellent AF performance with a new Group Area AF mode, so it’s a fine landscape and wildlife-action camera (although its 5 fps top shooting rate may not be enough for some action shooters). There’s 1080/60p video and time-lapse with exposure smoothing. The D810’s list price is $2,999. There’s also a D810A model, specially filtered for astrophotography.
The Df is a retro-designed model featuring a 16.2 MP sensor similar to the one in the D4S and an economical way to get that sensor’s good low-light capabilities. The D750 features a 24.3 MP CMOS sensor, 6.5 fps shooting and two exclusives for Nikon full-frame DSLRs: a vari-angle LCD monitor and built-in Wi-Fi. Finally there’s the D610, Nikon’s entry-level full-frame DSLR, with a 24.3 MP sensor, 6 fps shooting, 1080/30p video and a list price of under $1,500.
Sony a7R II
Besides making their own excellent full-frame sensors, Sony offers three types of full-frame cameras: SLT, mirrorless and all-in-one compact. The 24.3 MP SLT-A99 looks like a DSLR, but contains a fixed, semitranslucent mirror and an eye-level EVF, rather than the DSLR’s moving mirror and prism finder. This setup allows for full-time phase-detection AF and eye-level viewing in live-view operation, even for video.
There are three mirrorless models, two of which are available in both original and next-generation form. The flagship is the a7R II, with a backside-illuminated 42.4 MP AA-filterless CMOS sensor, 4K video capability (no external recorder needed), plus 1080/60p with full-frame readout and no pixel binning, and 5-axis SteadyShot INSIDE sensor-shift stabilization. There’s an eye-level EVF and a tilting LCD monitor, hybrid AF with 399 PDAF points, plus 25 contrast-based AF points, 5 fps shooting, built-in Wi-Fi and more. The a7R II has a list price of $3,199.
Other members of the a7 series include the original a7R (36.4 MP), a7S (12.2 MP, excellent high-ISO performance and full-pixel-readout video), a7 II (24.3 MP, 5-axis SteadyShot INSIDE) and original a7 (24.3 MP and a street price of $1,198—the lowest-cost full-frame camera as of this writing).
Sony also offers the virtually identical RX1 and RX1R all-in-one full-frame compact cameras, with 24.3 MP sensors, built-in Zeiss 35mm f/2.0 lens, 1080/60p video and 5 fps shooting, all in the smallest full-frame package: 4.5x2.6x2.7 inches. The difference between them is that the RX1R omits the AA filter. Estimated street price for both models is $2,798.