To study the affect of focusing with a wide aperture on a given scene, I selected a row of tree trunks against a garden wall. In order to emphasise the depth of field create by the wide aperture, a relatively acute angle was used.
Placing the camera on a tripod, I selected an aperture of f1.8 and then took a sequence of 11 images working from the right most focus point through to the left.
Below are 3 of the images taken with the focus point at the two ends and also the centre focus point:
In all three images, the eye is naturally drawn to the in focus area as a first point of reference. Once the eye has settled on the area of focus and has had chance to process the detail of the area, I find that the eye then begins to look at the remainder of the image looking for secondary sites of information.
The images with the focus points set at either end seem to give the least satisfaction and with these images the eye seems to move away from the point of focus much quicker than when looking at the image with the point of focus in the centre. This image holds the eye for slightly longer and I then find that the eye tends to move to the bricks protruding from the wall.
In this scene, these bricks seem to provide a natural point for the eye to fall upon and I feel this is where the focus point should ideally be, as shown here: