Even when used wide open at F/1.8 aperture, provides outstanding image quality with maximum aberration compensation, thanks to optimal use of sophisticated glass materials and highly advanced optical design
SP 45mm F/1.8 Di VC USD (Model F013) is a 10-element, 8-group construction, utilizing two molded glass aspherical elements and one LD (Low Dispersion) element.
Two of the aspherical elements effectively correct the field curvature to ensure planarity of the image plane, while efficiently compensating for spherical and comatic aberrations to achieve superb uniformity across the field with high-fidelity point spread reproducibility. Outstanding resolution is rendered from corner to corner and the sagittal comatic flare (a type of aberration that a point image at corners induces a comet tail-like blur), which tends to become prominently noticeable in night scenes, is thoroughly corrected.
The LD glass element optimally compensates for chromatic aberrations, which tend to become particularly prominent in fast-aperture lenses in general, and delivers crystal clear images without any residual color fringe.
World’s first* full-frame 45mm focal length with fast F/1.8 maximum aperture and integral VC (Vibration Compensation)
The aperture is optimized to F/1.8 to create the most practical lens offering superior imaging performance, a shorter minimum focus distance and image stabilization mechanism. Countless simulations during the design phase ensured the high resolution expected of a full-frame, high-speed lens coupled with spectacular background blur.
It is also the world’s first* full-frame, fixed focal length standard lens to be equipped with VC. Freedom in handheld shooting has been dramatically improved by reducing camera shake that tends to occur when using shooting in low light such as at dusk and in dark rooms. Also, the full potential of the high performance of the lens is realized by reducing minute vibrations that lower image quality conspicuous in high resolution cameras.
* As of July 2015; Tamron.
MOD (Minimum Object Distance) of 0.29m (11.4”), the best-in-class close focusing capability**
MOD measures 0.29m (11.4”), yielding a magnification ratio of 1:3.4, the best-in-the-class close focusing capability among fast-aperture fixed focal lenses in full-frame format**. The freedom of shooting at a closer distance to the subject expands photographic possibilities. Tamron’s proprietary Floating System, which places a group of elements at the optimal location as the focusing group travels relative to shooting distances, ensures the best imaging performance at any range. From the closest to a normal shooting distance range, excellent image quality is obtained.
** Rated top among current 45mm and 50mm fixed focal length interchangeable AF lenses for full-frame DSLR cameras excluding macro lenses (as of July 2015; Tamron).
Optimal relative illumination means no dark corners
Some fast-aperture lenses “vignette” or have darkened corners due to uneven light distribution.
However, even at the full open aperture, the overall illumination level across the entire field is well balanced and optimized. Because there is a sufficient amount of corner illumination, photographers can enjoy making full use of the wide open aperture.
eBAND Coating deployed to thoroughly suppress ghosting and flare
eBAND (Extended Bandwidth & Angular-Dependency) and BBAR (Broad-Band Anti-Reflection) coatings, both providing outstanding anti-reflection effect, are applied to critical element surfaces for maximum light transmission. Internal reflections from element surfaces which cause ghosting and flare are reduced to an absolute minimum. Flawless, crystal clear images can be obtained. eBAND Coating, a hybrid nano-structured layer with extremely low refractive index coupled with multi-layered anti-reflection coating technology, efficiently minimizes reflection of extremely angulated incident light—something that cannot be achieved by conventional anti-reflection coatings alone.
High-speed AF with USD (Ultrasonic Silent Drive)
Fast, quiet AF is achieved by employing a USD ring-type ultrasonic motor which enables remarkably precise focusing drive with high torque and responsiveness. Because the rotational torque of the USD is generated by waves of ultrasonic vibrations, inherent operating noise is extremely low and practically imperceptible. In addition, Full-time Manual Focus override is available at any point during the autofocus operation for deliberately shifting focus without switching the AF-MF mode back and forth.
Fluorine coating on the front element repels water and fingerprints
Fluorine coating technology, developed for use in industrial optics applications, has been adapted to photographic lenses. The water and oil repellant coating applied to the front element surface allows instant removal of dirt or smudges with ease. The coating also provides a reasonable level of durability, and will sustain its effectiveness for years.
Moisture-resistant construction for shooting outdoors under adverse weather conditions
Seals are located at the lens mount area and other critical locations to prevent infiltration of moisture and/or rain drops and provide moisture-resistant construction. This feature provides an additional layer of protection when shooting outdoors under adverse weather conditions.
Circular aperture for enhanced bokeh
The 9-blade diaphragm retains a nearly circular opening even when stopped down by two stops. Marvelously tuned blur in the subject background can be obtained without generating undesirable shapes of aperture patterns.
Compatibility with Adobe and Silkypix software
Supplied with SILKYPIX Developer Studio 4.0, advanced editing software that features correction menus for various aberrations (lateral color, distortion, relative illumination) based on the optical design data of this specific lens. Shooting RAW image files enables creation of more stringent and high-fidelity image quality.