Charlie,Originally Posted by cmcdarris
LF photographers are always trying to optimize aperture and shutter speed. The reasons for this are directly related to the size of the film (i.e., more important the larger the format). There are many situations where one simply can't stop down enough to get everything into sharp focus without either getting into diffraction degradation or ending up with a shutter speed that is impossible to use with a moving subject.
Firstly, as has been pointed out, the sharpest aperture for most LF lenses is around f/22. Ideally, one would want to shoot at that aperture or as close to it as possible. So, when the DoF at f/22 won't do the job, one can often use tilt and swing to reposition the plane of sharp focus in order to be able to shoot at f/22 or thereabouts. For many shots, especially those with tall objects close to the camera and important distant objects, there isn't much tilt you can apply. However, you'd be surprised how much even a little helps with aperture choice. I shoot architecture a lot, often a building with a bit of foreground. I can often save a stop or two by simply tilting the front standard so that the plane of sharp focus includes a close foreground object and the top of the building This then becomes my "near" and whatever is farthest from that becomes my "far." I can often reduce focus spread significantly (see the articles on the LF home page about focusing the view camera and choosing the f-stop). FWIW, however, my most used f-stop is f/32. This gives me prints up to 20x24 without enough diffraction degradation to bother me.
Secondly, we often have to use a faster shutter speed than would be optimal in order to stop movement in the scene, especially with landscapes. Wind, moving water, etc. require relatively fast speeds, which in turn, need wider apertures. Again, we can often use tilt/swing to reposition the plane of sharp focus to allow us to get the objects in the scene in sharp-enough focus and gain a stop or two wider aperture which can then allow the shutter speed to be faster.
A third consideration is image manipulation. Often we want to emphasize a foreground object, emphasize convergence or change the relative size of objects in the scene. This is done by tilting the back. Many use wide apertures and tilt/swing to manage the in-focus and out-of-focus areas in their images. These, however, are less-directly related to DoF and aperture size.
Hope this helps,
Doremus
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I think the image in the article was the first one in the gallery, "Zabriskie Point, Dawn" in case any are curious as to exactly which image you are referring to. 
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