Full-frame DSLRs are bigger and heavier than smaller-format cameras, but that full-frame sensor does make a difference in terms of image quality. That’s largely because a bigger sensor can collect more light, and more light means less noise and thus better image quality. Today’s top pro DSLRs are all full-frame models, so that’s the way to go if you’re into action or low-light work, not just low-ISO image quality.
If you shoot at a specific shutter speed and ƒ-stop in a given amount of light, the exposure will be the same for any format; the same number of photons per square millimeter will reach the sensor. But the full-frame sensor is larger than smaller sensors, so the full-frame sensor will collect more total (total light = photon/unit area times total sensor area). And more total light translates to a better signal-to-noise ratio because noise increases at the square root of the photon count: If 100 photons reach the sensor, there will be 10 photons of noise, for a photonic signal-to-noise ratio of 10:1. If 10,000 photons reach the sensor, there will be 100 photons of noise, for a photonic signal-to-noise ratio of 100:1. Of course, there are other sources of noise, but photonic noise (which is carried by the light itself and thus can’t be reduced by technology) is the major one for normal photography. More light = more image quality. (This, by the way, is why high-ISO shots are noisier: When you shoot at a higher ISO, you use a faster shutter speed and/or a smaller aperture, which reduces the amount of light.)
Of course, there are some things to keep in mind here. If you shoot at 1/500 at ƒ/2 with a full-frame camera and 1/500 at ƒ/2 with a Micro Four Thirds camera, the same amount of light will fall on each square millimeter of sensor area. Since the full-frame sensor is almost 4X the size of the M43 sensor, nearly 4X as much light will fall on it. But if you use the same focal length on each camera, the full-frame camera will produce a much wider angle of view because the larger sensor "sees" more of the image projected by the lens. If you want to produce the same framing with each camera, you’ll have to use a lens half as long with the smaller format: 12mm on the M43 camera, if you’re using 24mm on the full-frame camera. Now you have the same framing, but the M43 image will have more depth of field because that depends, in part, on the size of the aperture, and ƒ/2 on a 12mm lens equals 6mm, much smaller than ƒ/2 on a 24mm lens (12mm). If you want the same depth of field, as well as the same framing, with both cameras, you’ll need to stop the 24mm lens on the full-frame camera down to ƒ/4. If you then want to maintain the same exposure, you’ll have to slow the shutter speed on the full-frame camera two steps, in this case, to 1/125, so you get the same image brightness at ƒ/4. That’s fine if your subject isn’t moving, but may not work with an action subject. Of course, you could instead increase the ISO setting on the full-frame camera two settings and shoot at 1/500 at ƒ/4, but then you’re reducing the amount of light reaching the sensor, so the image will be noisier.
This works the other way, too. If you want the limited depth of field produced by a 24mm ƒ/2.8 lens wide open on a full-frame camera, you’d have to open the M43 12mm lens to ƒ/1.4—but there are no 12mm ƒ/1.4 lenses for M43 cameras.
For a very thorough explanation of equivalences, go to www.josephjamesphotography.com/equivalence. In practice, if you’re shooting with a given format, you’re setting everything to get the shot you want with that camera, not thinking about what you’d have to do to get an equivalent image with another format. A full-frame camera at a given shutter speed and ƒ-stop should produce better image quality (better signal-to-noise ratio, technology generation being equal) than a smaller format at the same shutter speed and ƒ-stop in the same light (but with less depth of field if you frame the image the same from the same distance).
Full-frame sensors perform better in low light than smaller sensors, in large part because they can collect more light at a given shutter speed and ƒ-stop. In DxOMark.com’s sensor ratings, the top 29 scorers in low-light ISO performance are full-frame ones. The highest-scoring APS-C sensor ranks 30th, the best medium-format camera, 37th (and that through pixel binning, which drops its 40-megapixel sensor to 10 megapixels), and the best Micro Four Thirds sensor, 78th. Note that DxOMark.com hasn’t yet tested the medium-format cameras using the new 50-megapixel Sony CMOS sensor, which should fare far better than the CCD sensors in low-light performance. In overall score, counting color bit depth and dynamic range, as well as low-light/high-ISO performance, full-frame cameras occupy the top 14 spots and 18 of the top 21. The other three are 40- to 80-megapixel medium-format cameras.
Full-frame DSLRs are available in resolutions from 12.4 to 36.3 megapixels. More megapixels mean the ability to record finer detail and make larger prints—assuming camera shake, poor focus and lens problems don’t destroy sharpness. More megapixels also mean larger files, which, in turn, require higher-capacity memory cards and archiving drives, and more powerful computers. Smaller pixels are less efficient than larger ones, but you have a lot more of them, so that sort of balances out. The four 36-megapixel full-frame cameras (the highest pixel count currently available in full-frame) hold spots 1 through 4 in DxOMark.com’s overall sensor ratings, followed by seven 24-megapixel full-frame sensors and an 80-megapixel medium-format CCD. The current 12-megapixel full-frame sensor rated 19th overall, but 1st in low-light/high-ISO performance.
Bottom line: All of today’s full-frame DSLRs (and mirrorless cameras—see the sidebar) are excellent choices in terms of image quality, whatever and wherever you shoot. And, of course, DSLRs are extremely versatile cameras, able to handle everything from studio still lifes to high-speed action, small enough to work almost anywhere, with a wide range of lenses from fish-eye to supertelephoto and good video capabilities. DSLRs are also good choices when you want to do selective-focus shots, or video, with minimal depth of field. If you do a wide range of types of photography, any of the full-frame DSLRs will serve you well. If you specialize in low-light or fast action, one of the under-20-megapixel ones would be the best choice. If you make huge prints or crop a lot or specialize in subjects with fine detail, one of the 36-megapixel cameras would be best.
Note that the full-frame DSLRs also have bigger, brighter viewfinders than smaller-format DSLRs, making it easier to compose images, track moving subjects and focus manually.
All of today’s full-frame DSLRs can shoot full HD (1920×1080) video except Nikon’s retro Df model. There are even two medium-format digital cameras that can do video (the Leica S Typ 007 and Pentax 645Z). There’s a lot to be said about video and sensor sizes. The very short and oversimplified story is that the big full-frame sensor delivers a cinema-like shallow depth of field you can’t get with a small-sensor video camera.
Canon EOS-1D X
Canon produced two versions of its flagship EOS-1 series pro DSLRs until mid-2012, one with an APS-H (1.3X crop) sensor and a high frame rate, and a high-megapixel full-frame mo
del with even better image quality. The EOS-1D X marked the merging of the 1-series into a single model. The 18.1-megapixel, full-frame EOS-1D X can shoot full-res JPEGs at up to 14 fps (with the mirror locked up and no AF) and full-res RAW (and JPEG) images at 12 fps with phase-detection AF for each frame—faster than the 16-megapixel APS-H EOS-1D Mark IV action camera it replaced.
Although 18 megapixels was somewhat less than many had anticipated for an EOS-1DS Mark III (21.1 megapixels) successor, it allows for the fantastic frame rate, as well as excellent high-ISO performance (normal ISO range is 100-51,200, expandable to 204,800), and is two megapixels more than Nikon’s flagship D4S. Also helping make the EOS-1D X Canon’s speed champ are two new-generation DIGIC 5+ processors, each 17X more powerful than the DIGIC 4s used in the previous 1-series generation.
The AF system features 61 points covering more of the image frame than its predecessor. Forty-one of the points are cross-types with lenses of ƒ/4 and faster, 20 are cross-types with lenses of ƒ/5.6 or faster (none were cross-types at ƒ/5.6 with previous 1-series cameras). A firmware upgrade added ƒ/8 AF capability—handy when using a teleconverter. The new system is also faster and more accurate than its predecessor, with a new AI Servo II tracking algorithm. The metering system features a 100,000-pixel RGB sensor and its own dedicated DIGIC 4 processor. The rugged pro body has 76 gaskets and seals to keep out moisture and dust, and a shutter rated at 400,000 cycles. A new quad-action mirror design reduces vibration and speeds operation (mirror blackout is just 60 ms).
Canon EOS 5D Mark III
The EOS 5D Mark II started the shoot-pro-video-with-a-DSLR phenomenon, and the Mark III improves on its predecessor in many ways. At 22.3 megapixels, the 5D Mark III is Canon’s highest-resolution DSLR. Its DIGIC 5+ is 17X more powerful than the DIGIC 4 in the 5D Mark II, which permits use of new noise-reduction algorithms, an improved video codec and even on-the-fly chromatic aberration correction. Normal ISO range is 100-25,600, expandable to 50-102,400. The 5D Mark III can shoot its 22.3-megapixel files at 6 fps, and sports the same high-density reticular AF system as the flagship EOS-1D X, with 61 AF points, a new AI Servo III AF tracking algorithm and the ability to work in light levels as dim as EV -2.
Like the EOS-1D X, the 5D Mark III offers 1920x1080p full HD video at 30, 25 and 24 fps, 1280x720p HD video at 60 and 50 fps, and 640×480 SD at 30 and 25 fps. Pro video features include All-I (for easy editing) or IPB (for smaller files) compression, Rec Run and Free Run timecoding, recording up to 29 minutes, 59 seconds at a clip (with automatic splitting of longer files), better image quality and audio volume adjustable during recording.
While not quite as rugged as the all-out pro EOS-1D X, the 5D Mark III is more durable than the 5D Mark II, with better weather sealing and a locking mode dial. The shutter is rated at 150,000 cycles. The 5D Mark III features the same 3.2-inch, 1,040,000-dot Clear View II LCD monitor as the EOS-1D X, great for live-view and video shooting (although it doesn’t tilt or swivel). There are slots for CompactFlash and SD/SDHC/SDXC memory cards.
Canon EOS 6D
Canon’s entry-level full-frame DSLR, the EOS 6D features good image quality and performance, built-in WiFi and GPS, and a very attractive price. The 20.2-megapixel 35.8×23.9mm CMOS sensor delivers 14-bit images measuring 5472×3648 pixels. DIGIC 5+ processing provides shooting at up to 4.5 fps and a normal ISO range of 100-25,600, expandable to 50-102,400. The 11-point AF system features a center cross-type point that works in light down to EV -3.
The big pentaprism viewfinder shows 97% of the actual image area, while the 3.0-inch, 1040K-dot LCD monitor provides easy live viewing. The compact (for a full-frame DSLR) body measures 5.7×4.4×2.8 inches and weighs 24.0 ounces. There’s no built-in flash, but there’s a hot-shoe for dedicated E-TTL II Speedlites.
A built-in GPS receiver records latitude, longitude, elevation and Coordinated Universal Time as EXIF data for easy geotagging. The EOS 6D is also one of the few full-frame DSLRs to offer built-in WiFi capability.
Video capabilities include 1080p at 30 and 24 fps (25 fps PAL) and 720p at 60 fps (50 fps PAL), plus 480p at 30 fps (25 PAL), all in H.264/MPEG-4 AVC High Profile (.MOV) form. Choose between All-I (better for editing) or IPB (more minutes per MB) compression, and Rec Run (during shooting only) or Free Run (full-time) embedded timecoding. Sound is mono via a built-in microphone or stereo via an optional external mic.
Like all full-frame EOS cameras, the 6D can use all Canon EF lenses, which currently range from an 8-15mm fish-eye zoom and a 14mm superwide-angle to an 800mm supertelephoto (and it can’t use EF-S lenses, which were designed specifically for the smaller APS-C sensors and would vignette if used on a full-frame camera).
Nikon’s flagship pro DSLR, the D4S improves on its D4 predecessor in a number of ways. It’s the quickest Nikon DSLR (11 fps at full-res with continuous AF, up from 10 fps in the D4), with even better high-ISO image quality (normal ISO range is 100-25,600, expandable to 50-409,600, both a stop better than the D4 and Df), thanks to a newly developed (but still 16.2-megapixel) FX-format (full-frame) CMOS sensor and EXPEED 4 processing. Low-ISO image quality has also been improved. The EXPEED 4 processing (vs. EXPEED 3 in the D4) combines with the improved sensor to make possible 1080 full HD video at 60p (up from 30p in the D4), with simultaneous writing to memory card and uncompressed output to external recorder via HDMI, when desired. The EXPEED 4 and a new EN-EL 18a battery also increase the shots per charge from 2600 to 3020 (per CIPA standard). While the basic AF system is the same as the D4’s (51 points, works down to EV -2 and with lens/converter combos as slow as ƒ/8), recalibrated AF algorithms and a new Group Area AF mode improve AF performance on moving subjects.
Retained are fine D4 features such as pro-grade construction and moisture sealing, a shutter tested to 400,000 cycles, a 3.2-inch 921K-dot LCD monitor and a bright pentaprism eye-level viewfinder that shows 100% of the actual image area. Subtle changes include grip modifications for increased comfort, improved ergonomics and shorter viewfinder blackout time for easier subject tracking.
Nikon’s third 36.3-megapixel full-frame DSLR, the D810 offers a number of improvements over its D800 and D800E predecessors. It completely does away with the AA filter (the D800E merely deactivated it), for even sharper image potential. It can shoot faster (5 fps at full resolution, 6 fps in 1.2X crop mode (25 megapixels) or DX mode (15.4 megapixels). Buffer size has been increased for longer bursts. New AF algorithms provide more precise autofocusing, even in dim light. The 51-point AF system includes 15 cross-type sensors and 11 cross-types that function at ƒ/8—ideal when using a teleconverter. There’s a new Group Area AF mode that’s great for action. The D810’s EXPEED 4 processing is 30% faster than its predecessors’ EXPEED 3, allowing for 1080 video at 60p and improved battery life (CIPA-rated 1200 vs. 900 shot
s per charge). A new electronic front curtain shutter minimizes vibrations to enhance sharpness. ISO range has increased at both ends (now 64-12,800, was 100-6400). You can now make up to 9,999 images in time-lapse/interval timer mode (vs. 99). Metering is Nikon’s 91,000-pixel 3D Color Matrix Metering III (II in the earlier models) to optimize exposure, AF auto white balance, i-TTL flash and subject tracking, all in a solid pro body.
The D810 can use more than 80 Nikkor lenses, including 65 FX-format (full-frame) ones. As with other Nikon full-frame cameras, if you attach a DX (APS-C) lens, the camera automatically crops to DX format to avoid image cutoff. FX lenses currently range from a 14mm ƒ/2.8 superwide-angle to an 800mm ƒ/5.6 supertelephoto, including true 1:1 macro lenses, lots of zooms, and wide, normal and short telephoto PC-E (tilt-shift) lenses.
The retro Df puts the 16.2-megapixel, full-frame CMOS sensor from the flagship D4 into a much smaller body with a design reminiscent of Nikon’s classic 35mm film SLRs, with simple control dials galore. But inside the very compact magnesium-alloy body is current high tech: 2016-pixel 3D Matrix Metering and a scene-recognition system, a versatile 39-point AF system with 3D Tracking and Auto Area AF, in-camera HDR, two- and five-frame auto-bracketing and more. EXPEED 3 processing optimizes image quality, and provides quick startup, 5.5 fps shooting and ISOs up to 204,800. And, in keeping with the back-to-basics theme, there’s no video. This is a digital camera for the old-school photographer who likes to control everything without messing with multiple menus.
Despite the retro look, the Df’s back is similar to other higher-end Nikon DSLRs, with a 3.2-inch, 921K-dot LCD monitor, a glass pentaprism eye-level finder that shows 100% of the actual image area and the usual DSLR buttons. But the top plate is where the action is. To the right of the pentaprism is a shutter-speed dial (4 to 1/4000 seconds, plus B, T and X, and a 1/3-step position). To the left are concentric dials: The top one contains exposure-compensation settings from +3 to -3, in 1/3-step increments. The bottom one sets ISOs, with normal range at 100-12,800, plus L1 (50) and H1 through H4 (25,600 through 204,800). Adjacent to the shutter-speed dial is the drive-mode switch (S, CL, CH, self-timer, mirror-up, etc.). To the right of the shutter button is a simple PSAM mode selector. The key point here is, you can set, and check, all of these settings without looking at the LCD monitor—actually, without even switching the camera on.
Nikon’s entry-level full-frame DSLR, the D610 provides excellent image quality on a budget, retaining the D600’s assets while adding a new shutter mechanism that ups maximum frame rate to 6 fps (from 5.5) and offers a new Quiet Continuous Shutter Mode with discreet shooting up to 3 fps. Like its predecessor, the D610 features a 24.3-megapixel, full-frame CMOS sensor and EXPEED 3 processing, with a normal ISO range of 100-6400 (expandable to 50-25,600). An updated algorithm improves white-balance performance, while 3D Color Matrix Metering II with a 2016-pixel RGB metering sensor handles the exposures.
Notable features for an entry-level camera include multiple-exposure capability, in-camera HDR, automatic time-lapse mode and intervalometer. A big eye-level optical viewfinder shows 100% of the actual image area, complemented by the 3.2-inch, 921K-dot external LCD monitor for live view and video shooting. The quick and accurate 39-point AF system is capable of autofocusing at ƒ/8, which is especially good for teleconverter users. In cropped DX mode, which the camera enters automatically when a DX lens is attached or you can select manually with any lens, the D610 produces 10.3-megapixel images with a 1.5X focal-length factor. (The viewfinder shows 97% of the actual image area in DX crop mode.) The D610 shares the ruggedness and dust/moisture resistance of the D600 (and D800), and its shutter is tested to 150,000 cycles. Top shutter speed is 1/4000. Video features include 1080p at 30 and 24 fps (25 fps PAL), and 720p at 60 and 30 fps (50 fps PAL), with continuous contrast-based AF during video shooting, when desired, and sound via a built-in mono microphone or an optional external stereo mic (there’s also a jack for headphones).
Nikon’s latest full-frame DSLR, the D750 is a step-up model from the entry-level D610, and probably a better first full-frame DSLR for a pro. With a similar 24.3-megapixel sensor in a similarly compact (but more rugged) body and EXPEED 4 processing, the D750 can shoot at 6.5 fps. It features the same metering and 51-point AF technology as the D4S and D810 (3D Color Matrix Metering II with 91,000-pixel RGB sensor and 51-point AF that can autofocus in light levels as dim as EV -3). Built-in WiFi makes for quick and simple wireless image transfer and remote control via smart device. Normal ISO range is 100-12,800, expandable to 50-51,200. The built-in flash has a Commander mode, so it can trigger external flash units with precise exposure and color information.
The 3.2-inch, 1229K-dot LCD monitor tilts—a first for a full-frame Nikon DSLR. Video features are the same as for the D810, including both 1080 and 720 at 60p, smooth time-lapse shooting and a built-in stereo microphone plus jacks for external mic and headphones.
The A99 is unique among today’s full-frame DSLRs in that it features a nonmoving, semitransparent mirror, rather than the conventional SLR flipping mirror. With the Sony TMT (Translucent Mirror Technology) system, most of the light passes through the mirror to the image sensor, while a portion is directed up to the phase-detection AF sensor. Thus, you get full-time phase-detection AF, even for video. Since this system would produce a very dim viewfinder image, the A99 uses a high-resolution electronic viewfinder instead of the conventional SLR optical finder. Therefore, you get eye-level viewing, even for video. For video and live-view still fans, this is an advantage: You can shoot videos of birds in flight, for example, something you really can’t do with conventional DSLRs, which have slow contrast-based AF and no eye-level viewing in Live View mode. The electronic viewfinder can also provide information an SLR prism finder can’t, including previewing white balance and exposure.
The A99 is ideal for action video due to the phase-detection AF and eye-level viewing. It’s good but not ideal for low-light specialists, due to the light lost to the semitransparent mirror.
|Full-frame cameras are also available in mirrorless form in Sony’s A7 series. The A7 II features a version of the Sony 24.3-megapixel Exmor sensor found in the A99, the A7R has a version of the very high-resolution Sony 36.3-megapixel sensor, and the A7S has a 12.4-megapixel Exmor sensor that delivers the best low-light ISO performance ever tested by DxOMark.com. The major advantages of the A7 series over the A99 are much smaller size, no light lost to the TMT mirror and, of course, the high-res and low-light sensors of the A7R and A7S. The major drawbacks are far fewer native focal lengths and slower AF pe
rformance. These cameras can produce outstanding image quality, but they may not be the best choices for action specialists.
Sony also offers the RX1 and RX1R full-frame compacts with a 24.3-megapixel CMOS sensor, differing only in that the RX1R has no AA filter. Featuring a built-in Zeiss T* 35mm ƒ/2 lens and a built-in flash, the cameras measure a minimal 4.5×2.6×2.7 inches and weigh 17 ounces including battery and memory card—remarkable for full-frame cameras.
|The main advantage full-frame DSLRs offer over smaller formats is better image quality. Medium-format digital cameras have much larger sensors and offer much better image quality at base ISO (usually around 50). At ISO 400, though, full-frame DSLRs take over because the CCD sensors used in medium-format cameras are optimized for low-ISO work. This is changing, though, with the recent introduction of Sony’s first medium-format sensor, a 44x33mm CMOS unit that should deliver much better high-ISO performance, along with excellent low-ISO image quality. Hasselblad and Phase One cameras and backs using this sensor have ISO ranges of 100-6400, while Pentax states a range out to ISO 204,800. Hasselblad’s H5D-50c camera and CFV 50c back, Pentax’s 645Z camera and Phase One’s IQ250 back all feature versions of this 50-megapixel CMOS sensor, tweaked to their own tastes. Leica’s new S Typ 007 features a 37.5-megapixel 45x30mm CMOS sensor with an ISO range of 200-6400.
Medium-format digital cameras are slower, bulkier and more costly than full-frame DSLRs. But speed doesn’t matter for the types of work medium-format shooters do (studio, portrait, landscape), and cost is coming down. Pentax’s first medium-format digital camera, the 645D, now sells for under $4,500, and the 645Z with 50-megapixel CMOS sensor sells for around $8,500 compared to the $40,000 you can spend for a high-end 80-megapixel CCD medium-format camera and back.