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p.5 #16 · 5D III Review: Wedding: Lots of issues!!! | |
Yakim Peled wrote:
Arun Gupta wrote:
James Cripps wrote:
"... though I have the last row of points to the left and right blinking and not available for my 24L and 70-200L 2.8. A bit sad about that...Sometimes when you go fast, your selection goes there and then you have to go back. Waste of time and a bit frustrating."
Sorry if this has been addressed. I'm just wondering what this is about? Why would any AF points be unavailable for the 24L and 70-200 f/2.8? I thought you would only lose AF at or beyond f/8 like an f/5 lens with an extender, etc.
While there should be no issue for the 24L v1 & 2, and the 70-200 f/2.8L, L IS, L IS II, pages 79 onward of the 5d3 manual divide lenses into groups A to H.
In group A, all the AF points work, including all the dual cross-type AF points. The lenses above belong to group A.
In group B, all the AF points work, but only the central dual cross-type AF point works as such. This includes the 14L, 15mm f/2.8 fisheye, the 24-70 f/2.8L.
In group C, all the AF points work but none work as dual cross-type AF points (yoiu still have a healthy array of cross-type AF points). There is a whole slew of lenses here including the 100mm f/2.8 L and non-L macros, the 500mm, 600 mm, 17-40 f/4, and various telephotos with extenders.
In group D, some of the outer cross-type AF points become horizontal AF points only, and so on.
While I must confess I'm disappointed to see such a big effect of the lens used on the AF system I'm amused to see the 50/1.8 in group A while the 800/5.6 is in group F and the 1200/5.6 in group G.
Happy shooting,
Yakim.
Right......the group F lenses have a good number of AF points deactivated, plus they do not have any double precision points. That's where 800 f/5.6 fits in.
Now, if anyone tells you that 800L is the best focusing Canon lens on their 5DMkIII, such as for birds in flight, they either do not understand, or they haven't got the experience or whatever, because there are several reasons why 800L is one of the worst performing BIF lenses I have experienced.......and I have used just about all of them starting with 15mm FE, except 600 f/4.
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