Another AF oddity / tip for X-Pro1 | Devwild on DPreview.com
Try laying the AF point across an area where the only contrast is a horizontal dividing line between two objects – in my case the top of a TV or picture frame vs the wall. The AF will struggle to focus, and depending on the circumstances, fail to lock more often than not. However, tilt the camera by 30-45 degress, or even 90 degrees, and it will lock – every time. Note that 90 degrees – horizontal lines don’t seem to cause a problem in portrait mode, only lines parallel to the long edge of the frame.
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