VII.NEW ACCESSORIES AND LENSES

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Canon EF 24mm This new wide-angle lens offers far more than a cosmetic makeover to the highly acclaimed f/1.4L II USM lens EF 24mm f/1.4L USM lens it replaces, and it retains the distinction of being the brightest

wide-angle L-series lens in its class. Added professional characteristics include dustproof and weatherproof construction, with dramatic improvements to image quality provided by a total optical re-design and the application of Canon’s exclusive Subwavelength Structure Coating (SWC) to the inside surface of the large front lens element. This special coating is designed to minimize ghosting and flare, especially from extreme off-angle light rays. It combines with traditional Super Spectra multi-coating, to give the lens unprecedented resistance to internal reflections and flare.

Ultra-low Dispersion (UD) glass lens elements were also added in order to reduce chromatic aberrations, and a high speed CPU and improved algorithms make possible a faster and quieter autofocusing system. Combined with two aspherical lens elements, the lens offers significant improvements in image quality and contrast, especially at the outer edges of the image when used on full-frame digital SLRs. A circular aperture means beautiful out-of-focus highlights in back- grounds. This new lens targets the critical professional photographer, and should be especially prized by users of high-resolution full-frame digital cameras like the new EOS 5D Mark II.

External View, Cross Section and Optical System of of EF 24mm f/1.4L II USM

EMD

Ring USM

Hood Mount

 

Distance scale

(Bayonet)

Distance scale

Depth-on-field scale

 

window

 

 

Infrared index

Contact

Focusing Ring

Distance Index

Focusing lens group (2nd lens group)

Focusing lens group (3rd lens group)

 

Image plane

 

Diaphragm

Lens mount index

Focus mode switch

UD lens

 

GMo aspherical lens

 

SWC-treated surface

BF=38.5mm

90.8mm

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Canon eos5d manual Emd