Decoding Sony alpha mirrorless camera lens designators
Frustrated when trying to find the right lens for your Sony alpha mirrorless camera?
“Vario-Tessar T* ZA OSS” – well, okay, how does that help me figure out if this is a good lens and what it features?
It’s just a bunch of alphabet soup, up until now.
Here’s your definitive guide to decoding the abbreviations and letters on Sony alpha mirrorless camera lenses.
For a primer on the differences between the Sony alpha mirrorless cameras, read An Easier Sony Alpha Mirrorless Comparison.
Mount & Camera
Sony mirrorless cameras use the E-mount. This differs from the Sony DSLR A-mounts, and you’ll need an adapter to interchange lenses. You’ll see “SEL” in the beginning of the short designation of any lens designed for mirrorless cameras. For example, “SEL1018F4” is a 10-18mm f/4 lens that will work on any Sony alpha mirrorless camera. The SAL1118 won’t work without an adapter because it indicates the A-mount.
All Sony E-mount lenses will either feature “FE” or “E” in the beginning of the name. “FE” indicates that it’s designed for the full-frame Sony alpha mirrorless cameras, like anything in the a7 line. Full-frame lenses can be used with APS-C cameras like the a6000, but the focal length will be increased by a factor of 1.5x.
Any lens with “E” in the beginning of the name means that it’s designed for the smaller APS-C sensors, such as the a6000, a6300, and a6500. An “E” lens can but mounted on an a7-series full-frame camera, but because the rear element is smaller, the camera will enter “APS-C” mode and reduce the size of the sensor & increase focal length. This feature can be disabled but you’ll get serious vignetting around the edges.
Sony’s top-of-the-line lenses are its Gold and Gold Master series lenses.
The Gold line of lenses were Sony’s first premium lenses for Sony alpha cameras. These lenses feature high-quality materials that reduce abberations and increase sharpness. Fast, constant apertures improve low-light performance and produce smooth bokeh and soft out-of-focus areas. “G” lenses can be identified by a white G on a black square. These lenses have now been moved to the second row with the introduction of the Gold Master series.
GM, or “Gold Master” lenses are an improvement on the G lenses and can be physically differentiated with a white G on an orange square. These lenses have been designed to focus faster in order to keep up with Sony’s improved focusing technology. They’re also more durable, improving resistance to dust and water. The lens elements reduce abberations even further, increase sharpness even more, and have better anti-reflective coatings. And they’re not cheap, either. The cheapest, a 100mm f/2.8, runs $1,499. The most expensive so far is the 100-400mm f/4.5-5.6 for $2,499.
Sony manufactures a line of lenses using Zeiss designs & technology – Zeiss is renowned worldwide for excellent optics. All Zeiss lenses will feature the design of the lens (Sonnar, Planar, etc), ZA, and T*. So, all of those designators are associated with the fact that it’s a Zeiss design. That knowledge should simplify things a tad.
You’ll see ZA towards the end of any lens designation featuring Zeiss design elements. Though not manufactured by Zeiss, these lenses have all been approved by and meet Zeiss’ high standards for quality lenses. The various Zeiss lens designs are explained below.
While you’ll see “ZA” in the full name of the lens, the short name will just have “Z” at the end – the 24-70mm f/4 ZA has the short designation of “SEL2470Z”.
This is another designation you’ll find on all Zeiss lenses. The front element of these lenses is covered in a proprietary anti-reflective coating developed by Zeiss. This coating reduces what’s known as “flare” and “ghosting” – those nasty artifacts scattered throughout the lens when pointed towards a bright point of light. This coating also reduces the haze that happens in those situations.
“Sonnar” is a Zeiss design from the mid-20th century. This popular design allows for a fast aperture in a compact, lightweight lens. It’s very popular for prime lenses, especially for portraits. Some of the best prime lenses for Sony alpha mirrorless cameras, such as the 55mm f/1.8, use the Sonnar design.
“Tessar” refers to a lens design developed by Zeiss engineers in the early 20th century. They allow for a relatively compact grouping with good quality at a reasonable price. The maximum aperture you’ll find on these lenses is f/4. The “Vario” prefix is used to indicate a zoom lens. My favorite wide angle zoom, the 16-35mm f/4, is a Vario-Tessar design.
The Distagon design is specific to wide-angle lenses. This lens design is relatively heavy and complex compared to other lenses of a similar focal length, but these extra design elements reduce aberrations and increase sharpness from edge to edge. The $1,599 Distagon T* FE 35mm f/1.4 ZA – a very fast, sharp lens – weighs 22 ounces and is over 4.5″ long by 3.2″ wide. Compare that to the $799 Sonnar T* FE 35mm f/2.8 ZA at 4.3 ounces and 1.5″ x 2.5″. But that increase in size & price may be worth it if the wide aperture and superb quality is what you need.
Yet another Zeiss design, and perhaps the oldest (dating back to the late 19th century), the Planar lenses allow fast apertures and increase sharpness all around. The only E-mount lens with the Planar design is the 50mm f/1.4. Not a small lens (almost 2 pounds and 4.5″ x 3.5″), but it’s super-fast, super-sharp, and produces very smooth bokeh.
Lens Design Elements
This one is kinda easy. OSS stands for Optical SteadyShot. These lenses feature stabilization gyros within the lens to give you a few extra stops of light while avoiding motion blur in handheld shots. This feature has become somewhat obsolete with the later generation of a7 cameras and the a6500, which feature 5-axis sensor stabilization within the camera. OSS and sensor stabilization can’t be used at the same time; errors in stabilization actually compound instead of making it smoother.
Power Zoom can be found on a few lenses in the E-mount lineup and are designed for cinematography. Zooming a lens by hand while shooting video can shake the camera and make the zoom jerky; the power zoom is activated by a switch on the barrel that will smoothly zoom the lens. One of the most popular PZ lenses is the E 18-105mm f/4 G OSS.
You’ve got me on this one. The only lens featuring this designator is the E 18-200mm f/3.5-5.6 OSS LE. This lens is touted by Sony as being their ultra-versatile, lightweight travel lens. So maybe “Lightweight E”? The SEL18200LE is only slightly smaller and lighter than the equivalently-priced SEL18200.
STF stands for “Smooth Transition Focus”. What’s that? This is a feature found on the 100mm f/2.8 GM lens. You can think of this as a way of fine-tuning the out-of-focus areas using aperture. Additionally, special lens elements will give these areas an exceptionally smooth out-of-focus area and transition.
Macro lenses are designed for taking close-up photos without distortion, and are capable of focusing very close to the camera (less than one foot).
Teleconverters, or TCs, increase the focal length of a lens. They’re a nice way of minimizing the amount of gear your carry, but at the same time reduce the amount of light that comes in. There are currently two teleconverters for Sony E-mount cameras, the 1.4x and 2.0x, but they’re only compatible with the 70-200mm GM.
Ultra Wide Converter
This converter attaches to the front of the 28mm f/2 and widens the view to a focal length of 21mm while retaining the optical quality of the 28mm lens.
This converter can be attached to the 16mm f/2.8 and 20mm f/2.8 to give you the wide “fisheye effect”.
Other lens abbreviations
You won’t see these abbreviations in the name of the lens, but you may see them in the description.
The supersonic motor is a specialized motor that quickly, accurately, and quietly focuses the lens. It’s a great feature in sports photography and other situations where quick focus is important.
The Direct Drive supersonic motor is a variant of the SSM featured on larger lenses – the heavier lens barrels require a bit of a more robust motor for fast & accurate focus.
Extra-low dispersion glass is a specially-designed lens element that reduces chromatic abberations – that purple fringing that often occurs around object edges in the outer area of the frame.
Anti-reflective coating is applied to Sony’s higher-end lenses to reduce flaring and haze; it’s similar to the Zeiss T* coating.
Extreme aspherical lens elements can assist in producing very smooth bokeh. You may have noticed that some bokeh in out of focus areas appear to have “rings” of different colors and shading within the bokeh. XA elements nearly eliminate this flaw. It also helps increase image resolution.
Does that all make sense now? What’d I forget?
For information on some of the best lightweight Sony alpha lenses best for backpacking & hiking, read this post of the same name.