Canon EOS-1V HS manual AF Sensitivity According to the Lens Maximum Aperture

Focusing an Off-Center Subject

AF Sensitivity According to the Lens' Maximum Aperture

The EOS-1V's focusing points are all horizontal-line sensitive. However, depending on the maximum aperture of the lens, certain focusing points can achieve higher AF precision.

(1) With lenses whose maximum aperture is f/2.8 or larger, the focusing points highlighted in the figure become cross-type sensors sensitive to both vertical and horizontal lines. The remaining 38 focusing points are horizontal-line sensitive. The sensor's vertical-line sensitivity is three times higher than the horizontal-line sensitivity. With lenses whose maximum aperture is f/3.5 or darker, all 45 focusing points will be horizontal- line sensitive except with the L-series lenses listed in (2) below.

(2) With the following Extenders and L-series lenses whose maximum aperture is brighter than f/4, high-precision AF is possible with the center focusing point working as a cross-type sensor. The remaining 44 focusing points are horizontal-line sensitive (except with EF 70- 200mm f/2.8L USM + Extender EF 1.4x).

·EF 28-80mm f/2.8-4L USM

·EF 300mm f/4L USM

·EF 300mm f/4L IS USM

·EF 500mm f/4L IS USM

·EF 600mm f/4L USM

·EF 600mm f/4L IS USM

·EF 70-200mm f/4L USM

•With Extender EF 1.4x:

·EF 200mm f/2.8L USM

·EF 200mm f/2.8L II USM

·EF 300mm f/2.8L USM

·EF 300mm f/2.8L IS USM

·EF 400mm f/2.8L USM

·EF 400mm f/2.8L II USM

·EF 400mm f/2.8L IS USM

•With Extender EF 2.0x:

·EF 135mm f/2L USM

·EF 200mm f/1.8L USM

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