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Sony introduced its first two full-frame mirrorless cameras, the Alpha a7 and a7R, to overwhelmingly positive reviews late last year. Revolutionary in many ways, the choices between the two cameras boiled down to the a7, which features a 24.3MP CMOS sensor, quick Hybrid Phase and Contrast autofocus, an electronic front-shutter curtain with Quiet Shutter Mode, faster top flash-sync speed (1/250 versus 1/160) , and slightly faster burst rates (5 fps versus 4 fps).
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The Sony a7R, which is a bit more expensive, features a higher-resolution 36.4MP imaging sensor with gapless on-sensor micro lenses, no anti-aliasing filter for sharper image detail, and a slower, yet eminently adequate autofocus system. Most importantly, both cameras take extraordinary photographs, 1080p AVCHD video, and are winning concepts in their own right.
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Adding to the excitement, Sony introduced the Sony a7S a few months later, which differs from its siblings by sporting a 12.2MP CMOS sensor with on-sensor micro lenses and an anti-aliasing filter, a maximum ISO sensitivity of an astounding 409,000, versus a maximum of ISO 25,600 on the A7 and A7R, and 4K video capture―when recording to an external recorder.
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Now the big question for consumers is, “Which Sony A7-series camera is best for me?” In this product review, we will attempt to clarify these issues. Be advised that the differences are not always cut and dried. There are enough overlapping attributes that make each of these cameras a smart purchase for most still- and video-capture needs. As for which camera is best for you, spend some time with the photo and video examples below, and read our recommendations on how to weigh the differences and similarities between these three camera systems.
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ISO Examples
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This series of night exposures was captured in an attempt to test the ISO performance of each of Sony’s three distinct a7-series cameras. Each camera was attached to the Sony FE 70-200mm f/4.0 G OSS lens and mounted atop a tripod via the lens’s tripod collar. Each camera was set to Aperture Priority mode and the lens was set to f/11.
A photograph was made at each full-stop ISO setting on each camera. This adjustment of the ISO inherently affected the shutter speed, which is apparent in the varying movement of New York's East River at the bottom of each frame.
Due to the complexity of lighting in this scene, and in an attempt to keep the highlights from being overexposed, the exposure compensation dial was set to -0.7 on each camera for every shot in the series.
The images you are seeing are RAW files, and were processed with Lightroom at a White Balance setting of 4500K.
As with every digital sensor, the image quality did slowly degrade as the test progressed and the ISO sensitivity was pushed to the limits on each camera. Each slide includes a native-resolution-crop image, so you can see more detail.
We think the results are very interesting, but we will let you decide which camera is right for your needs.
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Dynamic Range Examples
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A key attribute of an imaging sensor is the extent of its dynamic range. Dynamic range, i.e., the range of highlight, shadow, and mid-tone detail a sensor can capture, is a barometer of how detailed and "rich" an image appears. Because the 12MP imaging sensor in Sony’s a7S contains photo diodes (pixels) significantly larger than the photo diodes in Sony’s a7 and a7R (24MP and 36.4MP, respectively), the a7S has much higher sensitivity to light, making it the most viable available-light camera currently available from any manufacturer. As these images illustrate, Sony’s a7S can capture and display an extreme range of highlight and shadow detail without your having to resort to heavy image editing.
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Sony a7
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Sony a7S
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| Resolution Examples | |
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While it’s easy to soften or diffuse a photograph, the degree of sharpness in a photograph cannot be improved after the fact. The side-lit texture and forms of the marble columns along the entrance of the James Farley Post Office, in Manhattan, are perfect for evaluating the resolving power of each of Sony’s a7-series cameras. When discussing resolution, it’s important to note the degree of detail in the highlights, which can easily be blown out on lesser sensors, as well as the shadows. What’s equally important to note is the high levels of resolving power of which each of these cameras is capable.
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Sony a7
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Sony a7S
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| Vignette Examples | |
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This photograph of a rare open patch of Manhattan real estate illustrates how each of these cameras handles vignetting on wider-angle lenses. A notable issue concerning Sony’s a7 and a7R concerns vignetting and color shifting when using lenses wider than 25mm. One of the positive attributes of the Sony a7S is that, unlike the a7 and a7R, vignetting is greatly reduced, if not completely eliminated, when shooting with wide-angle lenses. These photographs, captured with a Voigtlander Super-Heliar 15mm f/4.5-L Aspheric lens, clearly illustrate the differences between each of these cameras in terms of wide-angle vignetting. | |
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Sony a7
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Sony a7R
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Sony a7S
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| Dynamic Range in Video Test | |
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| While all the a7 cameras have very good dynamic range in stills mode, in video it’s rather different. With the a7 and a7R you do have some control over gamma, because the creative-style jpeg profiles also influence the video. However, they don’t offer the best explanation of what they are doing with names like Night Scene, Sunset, Vivid, Clear, etc. For this test, the a7R and a7 are set to the Sunset creative style, which I think attempts to maximize the dynamic range. | |
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| On the a7S, there are much more precise picture profiles, with the ability to set knee level, black levels, gamma curves, and more. For this test, I shot the a7S in both Cine1 Gamma at a low ISO, and S-Log2 at ISO 3200 (3200 is the minimum ISO in S-Log2). The a7S has far more dynamic range in both modes, with S-Log2 having the most; however, it’s noisier in the shadows than Cine1 Gamma. | |
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| Rolling Shutter Video Test | |
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| In this test, all three cameras were mounted on top of each other to ensure that the panning speed was the same. All cameras are equipped with a Zeiss 35mm f/2.8 lens. | |
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| All three cameras suffer from rolling shutter, as do all CMOS-based cameras without a global shutter. However, the a7S is a little bit worse than the other two, probably due to the fact that it scans the entire sensor. In my experience shooting, this is the only area in which the a7S performed worse than the other two cameras in video mode, but it’s not terribly worse. To minimize rolling-shutter effects, wider-angle lenses work best, and lenses with IS should be used when handholding any of the cameras. | |
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| High ISO Video Test | |
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For this test, all cameras were set in the same night-scene creative style to test their noise performance at High ISOs. The reason a creative style was used instead of a more flattering gamma curve on the a7S is that crushing the blacks reduces the visible noise, as the shadows are typically the noisiest part of an image, so it makes the comparison fairer to use the same creative style on the a7S as the others. The scene was shot at night with the Voigtlander 35mm f/1.2. At ISO 3200, the lens is at f/1.2, and the lens is stopped down as the ISO is cranked up, until the end, when I open up to f/1.2 at ISO 409,600 on the a7S, just to see what it looks like.
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| As you might expect, the a7S wipes the floor with the other two cameras when it comes to high ISO in video. In stills at medium-high ISOs, the a7 and a7R aren’t that far behind the a7S once the 20MP and 36MP images are downsized to 12MP. Nonehteless, because they line-skip when shooting video, they aren’t actually using all of their pixels. Because of this, the a7 and a7R are already, in my opinion, only usable in emergency situations at ISO 6400 for video. Even ISO 3200 is really pushing it. The a7S is useable up to at least ISO 25,600. | |
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| Resolution and Aliasing Test | |
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This test shows both the difference in aliasing and moiré and the overall detail resolved by the different cameras. All cameras are equipped with the Zeiss 35mm f/2.8 and pointed at a scene with many fine details and fine lines. The brick building, fence, and lines on the gates are things to watch out for.
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| Aliasing and moiré will typically find themselves in any video camera, but the line skipping at the sensor level that most still cameras use when shooting video can lead to much more aliasing and moiré than when shooting stills. In this test, all three cameras show it to some degree, but it is far worse on the a7 and a7R then on the a7S, as is to be expected, since the a7S does not line-skip when shooting video. | |
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| Also, despite the fact that all cameras shoot video internally in 1080p, the amount of actual detail the cameras resolve varies by quite a bit. You can easily see by just looking at the bricks how much more detail there is in the a7S in 1080p, with the a7R coming in second, and the a7 coming in third. And if you need even more detail, the a7S can output UHD 4K video over HDMI. Unfortunately, portable UHD 4K HDMI recorders aren’t on the market yet. | |
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| The thing that surprised me most about this test was not how much better the a7S is than the others, since I was expecting that, but how much better the a7R is than the a7. The a7R resolves a lot more detail than the a7 and has less moiré and aliasing than the a7, as well. | |
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| Compression Video Test | |
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This test pitted the 24 Mb/s AVCHD video codec offered by the a7 and a7R against the higher-quality 50 Mb/s XAVC S codec offered by the a7S (although the a7S can record in AVCHD too, if you like). Traditionally long-GOP codecs like AVCHD and XAVC S struggle the most when there is a great deal of change between frames, as they try and record only the differences between groups of frames to save space. But since XAVC S has double the bitrate, it should be able to withstand twice as many changes without lowering the quality. I attempted to stress out AVCHD in two ways: first, with a high-speed object moving through the frame—a bicycle in this case—and the other by panning across highly detailed green foliage.
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| AVCHD held up pretty well in the bicycle test, probably due to the static background. On the foliage test there is a definite difference between the two, but it’s hard to say whether the better image coming out of the a7S is due to the fact that it resolves much more detail, or if it’s the AVCHD codec falling apart. Either way, the XAVC S codec is a welcome addition to the a7S. | |
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| New York at Night | |
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The excellent dynamic range and high-ISO ability of the a7S lends itself particularly well to street shooting at night, as streetlights and neon signs create very high-contrast environments. To showcase this, I shot a short at night. Most clips were shot with the a7S, but there are a few comparison shots thrown in, as well, to showcase just how different the a7S renders images in these high-contrast situations than the a7 and a7R. Also, it’s worth reminding people that the a7 and a7R aren’t bad at video—they perform at about the same level as other high-resolution still cameras that also shoot video. It’s just that the a7S performs at a different level.
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While the Alpha a7, a7R, and a7S share many qualities, they each offer specific features and specs that differentiate them from one another. The list below presents different kinds of photo and video work, and recommends the a7-series camera that's preferable for the application.
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Wedding and Event Photography
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For weddings and event photography, the Sony a7 and a7S are the best choices—the a7 for its faster autofocusing, and the a7S for its unrivaled low-light imaging abilities, 4K video capture, and a truly Silent Shutter mode.
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|  | Portrait and Fashion Photography | |
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The 36.3MP resolution and exacting details offered by its filterless design makes the a7R the clear choice for this application.
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Exception: if you shoot portraits or fashion outdoors, the faster maximum sync speeds of the a7 and a7S offer an advantage.
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|  | Landscape Photography | |
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With its high-resolution sensor and omitted anti-aliasing filter, the A7R would be a good choice for capturing the details usually important to landscape photography. In addition, fine art landscape photography is often printed in large format, which is supported by the high-resolution a7R.
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Exception: when shooting in locations with extreme contrast between the highlights and shadows, the high-dynamic-range capabilities of the a7S would retain more information in the shadows, without overexposing the highlights.
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|  | Photojournalism and Street Photography | |
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With the fastest continuous shooting rate and faster autofocus, the a7 is the way to go for street, documentary, and journalistic applications. In addition, a 1/250-second flash sync helps when shooting with fill flash outdoors, and the electronic first-curtain shutter provides more quiet activation. Normally, this type of photography does not require maximum resolution, and the faster processing speed of smaller files is an advantage in the news world.
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| Exception: the potential for damage on the street and in the field makes the magnesium-alloy, weather-sealed bodies of the a7R and a7S appealing. Plus, if the utmost silence is a concern, the silent mode on the a7S is a benefit. It is absolutely silent. | |
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|  | Still Life Photography | |
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Resolution and details are paramount in still life work and for this, the a7R with its 36.4MP filterless CMOS sensor, offers the highest resolution and superb details.
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Exception: if you're shooting still life in very low light, it might be worth considering the a7S with its low-noise, high-ISO capability.
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|  | Nature Photography | |
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The faster continuous shooting and hybrid autofocus system in the a7 allow you to capture images of fast-moving animals. Furthermore, the AF Predictive Control feature on the a7 recognizes movement to or away from the camera and calculates where the subject should be in the instant between continuous shots.
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Exception: the a7S has the advantage of better battery life, which will help on long outings into the woods. It also has the silent mode, which is clearly an advantage when photographing wildlife.
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|  | Documentary Video | |
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For shooting talking head interviews and controlled B-Roll footage, the a7S is a great documentary camera. A full-frame sensor makes it easy to shoot interviews with a defocused background, even in cramped spaces. The high dynamic range and more flexible picture profiles allow you to get B-Roll footage in almost any environment without setting up lights. All three cameras are also compatible with Sony’s XLR adapter, making it easy to get good audio without having to sync in post.
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Exception: if you will be shooting handheld, run-and-gun work, consider the a7R. Its rolling shutter is a little better (fast pans and shaky hands don’t mix well with rolling shutters). Plus, the softer overall image on the a7R makes focusing on the fly a little more forgiving.
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|  | Film Students | |
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A helpful aspect of the a7-series cameras is that they handle very similarly. They all have the same control layout, the same focus aids, they use the same lenses, and have the same-sized sensor. Once you get used to shooting with one, it’s easy to move to another. Because of this, the a7 might be the best choice for film students. It's significantly cheaper than the a7S or a7R, and the differences in video image quality won't impede your creativity. Having an extra $1,000 to spend on lenses shouldn’t be overlooked.
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Exception: if your budget isn't a barrier, the a7S is the best overall video camera.
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The gift-giving season is upon us. Chances are you’re one of the millions of people shopping for a new digital camera this year. Whether for a friend, a loved one, or you’re simply spoiling yourself, tackling the ever-changing and expanding market can be daunting.
So where to start? There’s no overly specific technical formula for buying a camera. Be sure to do thorough research and ensure that your purchase offers the specs you need. Is built-in Wi-Fi important? What about internal memory, or the ability to shoot video in Full HD 1080p? Pay attention to details, and figure out what it is that will best suit you, or whoever will receive your gift. In the meantime, here are a few general pointers to get you started.
Megazoom compacts offer a much longer zoom range, hence the name, for easier access to far-away subject matter. These are handy for anyone who regularly takes photos at concerts or sporting events, for example, and wants to capture shots from a distant viewpoint. They also include a few more options for manual operation, though image quality is relatively consistent with the basic point-and-shoots with which they share the spotlight. The Canon PowerShot SX50 HS is hefty, which may be a draw to those looking for an impressive-looking device. It has 50x optical zoom and a swivel LCD screen.
In a similar light, the Nikon COOLPIX P520 has a 42x zoom and swivel, vari-angle LCD screen. The Pentax X-5 offers a 26x zoom lens and tilting LCD screen.
Advanced compacts are perfect for anyone looking to upgrade to a more advanced system that still remains sleek and comfortable in size. These cameras tend to have larger image sensors and faster processors, which yield higher picture quality and better low-light performance. They offer more options for manual control, and many today are fully capable of shooting in RAW format. One of these would be an excellent gift for enthusiasts who enjoy photography with purpose, and might later want to make adjustments in post-processing. The Canon PowerShot G16, which has built-in Wi-Fi, employs Canon’s Intelligent IS system for sharper images taken in low-light environments. The Nikon COOLPIX A comes with a dedicated 18.5mm wide-angle Nikkor lens that packs superior optics into a small package. The Leica C’s beauty matches its performance in eye-catching dark red and light gold.
Professional DSLRs, such as the Canon 5D Mark III, Sony Alpha A99, or Nikon D800, are for photographers who need cameras that can stand up to the rigors of daily use and are durable and efficient, consistently capturing images of professional quality. They maintain excellent processing speed, quick autofocusing, and optimal low-light performance. Full-frame image sensors, while not as critically important to some people as others, do tend to respond better to higher ISO settings and boost overall image quality. Full-frame cameras also enable photographers to use a variety of lenses without needing to account for a crop factor; something especially important to anyone regularly shooting wide-angle images.
If you’re shopping for lenses instead, take the same factors into account that you would for choosing a camera. Fixed focal length, or prime lenses, are generally less expensive than zooms, but can also be somewhat limiting depending on how they are being used. Heavy-duty, weatherproof lenses, such as those in the esteemed Canon L-series lineup, will bear a price tag that reflects their higher quality. Dedicated lens manufacturers such as Tamronor Sigma also offer a huge selection of great “off-brand” glass that can end up saving money on a purchase. Once you factor in budget, you can further narrow your choices. Assuming that you or whomever you’re shopping for do not already own an extensive lens collection, there are several things you can keep in mind to help expedite the process. For shooting insects, flowers, and other tiny details, a dedicated macro is a fantastic choice. Every photographer who loves broad landscapes or architecture needs a decent wide-angle lens. When shooting a distant subject, such as wildlife or sports, a sharp, fast telephoto is second to none. Lastly, standard- and medium-length telephotos make fantastic “walk-around” lenses for everyday applications and portraiture. Additional things to consider include maximum aperture (the wider, the faster), image stabilization technology, and autofocus motor.
viewfinder. Instead, they operate similarly to a point-and-shoot, with light falling directly onto the image sensor. This allows shots to be “previewed” on the camera’s LCD screen before each click. Eliminating the bulky mirror and shutter components makes their bodies much smaller and lighter than their DSLR contemporaries. With mirrorless systems, photo enthusiasts and professionals are given the freedom to shoot RAW and capture high-resolution images without toting bags of heavy gear.
The Pentax Q10 has a relatively small 1/2.3” image sensor, and is compatible with all Pentax Q-Mount lenses, as well as K-Mount lenses with the properadapter. The Olympus OM-DE M1 is an indication of mirrorless cameras’ rapid improvement in technology and design. Whereas many mirrorless cameras face slower autofocusing (especially in low light), the OM-DE M1 rivals the speed of a DSLR by employing both contrast and phase detection AF. It accepts lenses designed for the Micro Four Thirds System.
Sony garnered the attention of the photography community when it released the full-frame a7 and a7R this fall. The a7R omits the optical low-pass filter of the a7. This increases resolution, enabling superb sharpness in even the finest details. Both cameras are compatible with Sony E-Mount lenses. Much like DSLRs, mirrorless cameras can range in cost, and lens expenses must be factored in separately.
It easy to get overwhelmed by the sheer number of cameras on the market, but have no fear: with some basic research, you can easily analyze your budget and needs to score the perfect gift. If you need more guidance, contact B&H for advice.
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