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Paul Villiger
23.06.2005, 10:30
Kann mir vielleicht jemand helfen? Ich bekomme morgen die Kamera und habe noch die Wahl der Canon Objektive (im mom Tamron). Nun verstehe ich die Aussage nicht: "maximum aperture of F2.8 or faster". Bedeutet dies, das das 17-40L dies: "to both horizontal and vertical detail" nicht zulässt?

Danke für Eure Hilfe.
LG
Paul

Auto Focus

<TABLE cellSpacing=1 cellPadding=6 width=480 align=center border=0><TBODY><TR><TD class=tdcontent>http://www.dpreview.com/reviews/canoneos1dmkii/Images/45areaafcmos.jpg</TD><TD class=tdcontent>http://www.dpreview.com/reviews/CanonEOS1DMkII/Images/crossafpoints.gif</TD></TR><TR vAlign=top><TD class=tdlabelsimpsm>Auto Focus sensor (CMOS)</TD><TD class=tdlabelsimpsm>Cross-type sensors (horizontal and vertical sensitive) only with lenses with max. aperture of F2.8 or faster</TD></TR></TBODY></TABLE>

The EOS-1D Mark II uses the same 45-point area AF CMOS sensor used in the EOS-1D/1Ds, it measures 15 x 8 mm and is located just below the semitransparent mirror and receives the exact same image you see through the viewfinder.

All AF points are sensitive to horizontal detail, however for a lens with a maximum aperture of F2.8 or faster lens a vertical row of 7 points (as indicated in red in the diagram above, right) become sensitive to both horizontal and vertical detail, and the manual notes, are three times more sensitive than the normal horizontal sensors. Some other L lenses with maximum apertures of F4 or brighter make use of the center cross-type AF point.

MarcusMueller
23.06.2005, 10:36
Ja, das ist völlig richtig: Kreuzsensoren außen nur mit <= 2,8.

Stört in der Praxis aber auch nicht weiter.

Gruß, Marcus

Paul Villiger
23.06.2005, 22:49
Besten Dank für die Info

Paul