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<blockquote data-quote="aroy" data-source="post: 315638" data-attributes="member: 16090">It is an individual lense and camera combination.The back/front focusing is when the Auto Focus focuses behind/ahead of where it is supposed to focus. This is mainly a camera-lense combination problem. The lense servo may be maladjusted so that it sets the lense focus away from where it was supposed to be. Most high end cameras have a facility to enter a number (+ or -) which shifts the focus. In low end camera it is not there.You take a shot of an inclined scale (with the top away from you and the bottom towards you) and focus at a graduation, say XXX. If there is back focus, then the graduations above XXX will be in focus, if there is a front focus then the graduation below will be in focus. The job of the fine tuning of focus in camera is to shift the focus (in the lense) to compensate for this error. What number to dial is explained on the net in details (Lens Align is one such product which has extensive details on its site).Ultimately for critical focus, as in Macro, it is best to use manual focus for the fine tuning. The AF is pretty coarse and when the object is small and angular, it may not know where exactly you want the focus to be.</blockquote>

[QUOTE="aroy, post: 315638, member: 16090"] It is an individual lense and camera combination. The back/front focusing is when the Auto Focus focuses behind/ahead of where it is supposed to focus. This is mainly a camera-lense combination problem. The lense servo may be maladjusted so that it sets the lense focus away from where it was supposed to be. Most high end cameras have a facility to enter a number (+ or -) which shifts the focus. In low end camera it is not there. You take a shot of an inclined scale (with the top away from you and the bottom towards you) and focus at a graduation, say XXX. If there is back focus, then the graduations above XXX will be in focus, if there is a front focus then the graduation below will be in focus. The job of the fine tuning of focus in camera is to shift the focus (in the lense) to compensate for this error. What number to dial is explained on the net in details (Lens Align is one such product which has extensive details on its site). Ultimately for critical focus, as in Macro, it is best to use manual focus for the fine tuning. The AF is pretty coarse and when the object is small and angular, it may not know where exactly you want the focus to be. [/QUOTE]

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