Of course, when bystrouskolzayuschem story should use auto focus (if any), and probably no time to mess around with switching focus areas. Better to leave the central narrow band (to avoid overlaps and errors), and drove the main object in the center, avtofokusirovat, assemble and quickly 'flip'. When moving the main subject autofocus will also be more reliable, and wide area so as not to lose the object. But when slowly and smoothly changing the plot, with the staging work better to use manual focus in the final frame your subject. And even if the main object is located in the central zone, manual focus, in many cases may remain preferable.
Lawless because automation is induced, for example, strictly eyes – as well it might lead to the nose or ears. And for this we must add the appropriate vigilance eye, otherwise – af remains out of competition. If there is no autofocus, and the quality Screen on the periphery of poor, it should at least try to focus on it as the periphery of which focus more acceptable. One of the most extensive areas focusing on the present day – with cameras Canon EOS-1V and eos 3. It is formed by 45 separate sensors. Such abundance markedly enhances photographers in terms of focusing on objects located in the peripheral parts of the frame.
On the alignment of focusing screen. I do not think that this problem relates to modern and even 'old' camera''Brand-Name '. But here's to the 'old men' and domestic Zenith and other former national photographic technique is of direct relevance.