Sony Alpha E-Mount Sonnar T* FE 35mm f/2.8 ZA Lens
Outstanding Zeiss optical performance in a versatile
35mm focal length & bright f/2.8 maximum aperture.
The small size, Sonnar T* FE 35mm F2.8 ZA features a versatile 35mm focal length, and outstanding overall performance of this Carl Zeiss Sonnar T* lens make it an ideal match for compact 35mm full frame format E-mount bodies. Although the optical design is state-of-the-art, this superb wide angle lens remains true to the original Sonnar concept with a bright F2.8 maximum aperture ("Sonne" means "sun" in German). Three double-sided aspherical elements minimize aberration so that stunning contrast and resolution are maintained right out to the image edges at all apertures. The renowned T* lens coating contributes to natural color reproduction as well.
A perfect match for Alpha series full frame E-Mount bodies
The handling and convenience of this wide angle lens for 35mm full frame format bodies is significantly improved by the use of an internal focus mechanism that keeps the length of the lens constant during focusing. The light weight of this model also enhances portability as well as handling. All of this plus compact dimensions and outstanding image quality make the SEL35F28Z an ideal match for the full-frame A7-series full frame E-mount bodies.
Carl Zeiss quality
Outstanding resolution and contrast are the key features of this lens. Three double-sided aspherical elements (six aspherical surfaces) effectively control spherical aberration, while extensive application of the Zeiss T* coating not only minimizes flare and ghosting for natural color reproduction, but is instrumental in achieving impressive contrast as well.
Bright F2.8 maximum aperture
A bright maximum aperture of F2.8 enhances shooting convenience, particularly since the same high image quality is maintained at all aperture settings. Bright lenses usually end up being physically large, but in this case a new focus lens group design has made it possible to achieve a large maximum aperture in a compact unit. A circular aperture design delivers gorgeous bokeh for smoothly defocused backgrounds.
Dust and moisture resistant design
Like the A7-series full frame E-mount bodies, critical areas of the lens exterior feature dust and moisture resistant seals that help to ensure reliable operation even in adverse environmental conditions. The lens exterior features an elegant aluminum finish, adding sophistication that is consistent with the high quality standards implied by the Carl Zeiss name.
Unmatched T* (T-star) coating
The fact that lens coating technology - vapor deposition of a thin, even coating on the lens surface to reduce reflections and maximize transmission - was originally a Carl Zeiss patent is well known. The Carl Zeiss company also developed and proved the efficacy of multi-layer coatings for photographic lenses, and this is the technology that became the T* coating.
Aspherical lens elements
Spherical aberration is a slight misalignment of light rays projected on the image plane by a simple spherical lens, caused by differences in refraction at different points on the lens. That misalignment can degrade image quality in large-aperture lenses. The solution is to use one or more specially shaped "aspherical" elements near the diaphragm to restore alignment at the image plane, maintaining high sharpness and contrast even at maximum aperture. Aspherical elements can also be used at other points in the optical path to reduce distortion. Well designed aspherical elements can reduce the total number of elements required, thus reducing overall lens size and weight.
Only the middle groups of the optical system are moved to achieve focusing, which leaves the total length of the lens intact. Benefits include fast autofocusing and a short minimum focusing distance. Also, the filter thread at the front of the lens does not rotate, which is convenient if you're using a polarizing filter.
In general, if an aperture uses 7 or 9 aperture blades, then the shape of the aperture becomes a 7-sided or 9-sided polygon as the aperture is made smaller. However, this has a certain undesirable effect in that the defocusing of point light sources appears polygonal and not circular. Alpha lenses overcome this problem through a unique design that keeps the aperture almost perfectly circular from its wide-open setting to when it is closed by 2 stops. Smoother, more natural defocusing can be obtained as a result.