Objektivskolan - Ordlista - SD (Tokina)

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SD = Super Low Dispersion

Förklaring från Tokina

When standard optical glass is used in telephoto lenses, a phenomenon called chromatic aberration can occur. Chromatic aberration is the inherent tendency for glass to disperse (separate) a ray of light into the colors of the rainbow. The rainbow effect created by a glass prism is the most dramatic demonstration of chromatic aberration. In lenses, it is much less pronounced, but still creates slightly out of focus colors, akin to an “optical noise” that has a negative impact on the quality of the picture. To eliminate chromatic aberration, Tokina employs expensive, special glass material having super- low dispersion (SD) properties.

Lenses in the Tokina line-up with the SD mark incorporate these Super-Low Dispersion glass elements, minimizing the secondary spectrum or optical noise caused by chromatic aberration.

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)
	Sigma EX 70-200mm f/2,8 APO HSM DG OS
	Sigma EX 28mm f/1,8 DG ASP Macro
	Sigma EX 120-300mm f/2,8 DG OS APO HSM
	Sigma EX 120-300mm f/2,8 APO DG HSM

Objektiv för Nikon
Nedan visas några populära alternativ (se alla)
	Nikon AF-S 70-200mm f/2,8 G IF-ED VR
	Nikon AF-S 70-200mm f/4 G ED VR
	Sigma EX 50-500mm f/4-6,3 DG APO OS HSM
	Nikon AF-S 24-85mm f/3,5-4,5 G ED VR

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