Objektivskolan - Ordlista - AS (Tokina)

 
Förkortningen betyder
AS = Aspherical Optics
 
 
Förklaring från Tokina
A standard lens is made up of a combination of spherical lens elements. Individual “lenses” within the lens are commonly referred to as “elements”. A spherical element has an even curve to the surface of the glass. However, there can be problems with such elements; light entering the center of the lens and light entering at the edge may not be perfectly focused at the same point. This is called spherical aberration. More advanced computer assisted optical designs are creating lenses with more spherical elements. More spherical elements within a lens means a greater risk of spherical aberration having a negative impact on optical quality.

Wide-angle zoom lenses and wide-angle lenses with large apertures are especially at risk for spherical aberration.

To eliminate spherical aberration, Tokina employs aspherical all-glass elements in many of its optical designs to correct this problem. The aspherical shaped surface of the lens element focuses light rays entering both the center and edge of the element correctly at the film plane for an accurately focused image. In addition to correcting spherical aberration, these elements fully correct light quantity and distortion at the edge of the image and provide excellent results when used in combination with a floating element design.

Through a close collaboration with Hoya Corporation, the world’s largest optical glass manufacturer, Tokina has succeeded in producing high quality precision molded all glass elements with a greater aspherical shape than any other lens manufacturer. This technique is unparalleled in its technological sophistication and precision.
 
 
Se exempel på berörda produkter
Tokina AT-X 16-28mm f/2,8 PRO FX
Tokina AT-X Pro 16-50mm f/2,8 DX
 
Se länkar
tokinalens.com




Objektiv för Canon
Nedan visas några populära alternativ (se alla)
Canon EF TS-E 17mm f/4 L Canon EF TS-E 17mm f/4 L
Tokina AT-X Pro 12-24mm f/4 DX II Tokina AT-X Pro 12-24mm f/4 DX II
Canon EF 800mm f/5,6 L IS USM Canon EF 800mm f/5,6 L IS USM
Canon EF 70-200mm f/2,8 L IS USM Canon EF 70-200mm f/2,8 L IS USM
 
 

Objektiv för Nikon
Nedan visas några populära alternativ (se alla)
Tamron SP AF 24-70mm f/2,8 Di VC USD Tamron SP AF 24-70mm f/2,8 Di VC USD
Nikon AF-S 200mm f/2 G ED VR II Nikon AF-S 200mm f/2 G ED VR II
Nikon AF-S 200mm f/2 G IF ED VR Nikon AF-S 200mm f/2 G IF ED VR
Nikon AF-S 70-200mm f/4 G ED VR Nikon AF-S 70-200mm f/4 G ED VR
 
 

Objektivskolan
Våra artiklar utbildar dig (se alla)
Skydda ditt objektiv med ett filter
Att rengöra ett objektiv
Kameran kan påverka brännvidd
Se bilder tagna med en viss brännvidd
Se objektiv för just din kamera
Nedan visas några modeller (se alla)
Canon EOS 1D X Mark II
Canon EOS 850D
Canon EOS 5DS R
Nikon D750

Nyheter
Nikon AF-S 600mm f/4 E FL ED VR

Nikon AF-S 600mm f/4 E FL ED VR
Nikon AF-S 500mm f/4 E FL ED VR

Nikon AF-S 500mm f/4 E FL ED VR

Två populära objektiv du inte får missa
Canon EF 16-35mm f/2,8 L USM II

Canon EF 16-35mm f/2,8 L USM II
Canon EF 17-40mm f/4 L USM

Canon EF 17-40mm f/4 L USM

Senast besökta objektiv
Nikon AF-S 24mm f/1,4 G ED

Nikon AF-S 24mm f/1,4 G ED
Nikon AF-S 105mm f/2,8 G IF-ED Micro-Nikkor VR

Nikon AF-S 105mm f/2,8 G IF-ED Micro-Nikkor VR

Senast besökta kameror
Canon EOS 50D

Canon EOS 50D
Canon EOS 650D

Canon EOS 650D
Nikon D5

Nikon D5








Copyright © Objektivguiden 2020 Om Objektivguiden