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Message: <blockquote data-quote="tdodd" data-source="post: 1295951" data-attributes="member: 55450">If I missed this point then I apologise, but do you understand that when you use AI Servo with all focus points enabled you must first lock focus with the centre focus point. You can't just wave the camera in the general direction of what you want in focus and expect the camera to know what you want it to focus on. The camera does not look for movement. It focuses on whatever is under the active focus point. It has to start from some known point and, if you have all FPs enabled, that is the centre FP. If you pick a single active focus point, rather than all of them, then that is the only focus point the camera will use. It will not hand over AF to the other points. If your subject is large enough to cover the centre point and also one of the other focus points then, when the subject slips off the centre point the AF will continue with the other focus point(s) that still cover the subject. If the subject is too small in the frame to cover more than one FP at the same time then once it falls through the gaps between them you will lose AF. You need to release the AF button, re-acquire the target with the centre point and then resume AF. If your camera/lens combination is really front focusing by 14mm then it could be the camera, or the lens, or both that is/are miscalibrated. Unless you have another body and another lens to swap with I don't see any way that you can conclusively decide which is at fault. As for metering, which metering mode are you using - spot? If so, expect erratic results if you are not metering off the right target. If you didn't intend to use spot metering, could you have set the camera to spot metering, or even partial, by accident? FWIW I have a 30D (2+ years old), a 40D (1 year old) and six canon lenses, including the 100-400 and I have never had problems with any of my kit. Your story of the agent's handling of this is quite disgraceful. They sound like idiots. I hope you have good fortune sorting out your problems.</blockquote>

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