Please answer the questions: some questions when shooting Canon 550D.

First, the first question. Personally, I think it's best not to use autofocus when taking pictures. More accurate. The autofocus point focuses too much and the diagonal line is not accurate.

Secondly, the aperture of f4 is a little too big. Personally, I think it should be at least f8, but it also depends on the actual situation. You can take more photos to see the effect. Try a few more photos of this thing to estimate the effect.

As for the problem of metering, if it is not very professional, just use evaluation, and focus on metering in the center until you reach a certain level.

The less sharpness, the more fleshy the film is. The greater the saturation, the brighter the color.