When starting out in LF, most start out trying to use far more camera movement than needed to accomplish our objective (no pun intended). Here's an example of how it could become confusing, which I happened to recall today from my own past experience. Perhaps it will help someone new to LF photography.
I was using a 210mm lens on a country scene. I was by a road on a low hillside. A barn with tall trees close by it stood perhaps 1,000 ft. or more away, on high ground about the height level at which I was standing. In between, the ground in front of me as I faced the barn sloped down to the level of a large pond, perhaps 20 feet below. The closest grass in my composition remained at about my level and lay perhaps 20 feet from the lens. I wanted everything in focus.
From under the dark cloth, I started by tilting the lens enough to have the center of the barn and the nearby grass simultaneously in focus. However, the pond was then way out of focus. But what astonished me, was that shifting the focus to the pond at this setting required moving the front standard backward, i.e., the pond was now the far focus and the distant barn the close focus. Huh?!
The key to the conundrum is to remember what happens as we tilt (or swing) either standard. Imagine two marks painted on the plane of focus, one at the top of your framing, the other at the bottom. For simplicity, let's assume that the lens will be tilted around its center. Starting at vertical with the camera levelled and movements zeroed, as we slowly tilt the lens forward, the plane-of-focus starts tilting (more than our lens board) from vertical increasingly toward horizontal, the imaginary top mark moving farther away from the camera and the bottom mark getting closer to the camera. "Far" focus will remain on the far side of the plane, which will be increasingly underneath the titling plane; "near" focus will remain on what was our side of the plane, and thus increasingly above the tilting plane.
The cause of the seemingly opposite focusing direction in the scene described, was the degree of tilt. By tilting so much that the grass and barn were simultaneously in focus, the plane of focus had been made nearly horizontal. Therefore, I was actually focusing on the distance from the camera to the grass in an almost vertical direction, just as if, had I used no movements, I would have had to aim the camera down toward the grass mot far from the front foot of the tripod. With the plane of focus in this orientation, therefore, in order to bring the pond into focus meant focusing farther away (thus bringing the lens closer to the film), because the pond surface surface, about 20 feet below my feet, now lay on the far side of the plane of focus, which had been place somewhere around 7 feet from the lens.
In my case, the picture I had hoped for was not really within the capabilities of the lens. The depth-of-field I wanted would have required an f/ stop of about 64, and even if I had had it marked on my lens, the diffraction would have surely taken the edge off the crisp Ansel Adams look I was imagining.
I hope this may be useful.
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Originally Posted by Ulophot
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