Framing and cropping
A natural frame can be used to emphasize the subject of a photo. This first pair of photos are the same shot. In one, the trees and leaves frame the stormy sunset over the lake. In the other, several of the plants have been removed and the image has been cropped.
The frame of trees changes the character of the photo completely. The subject is the same either way - a lake during a stormy sunset - but what changes is how the viewer feels while looking at the photo. The photo with the frame has more depth and also makes it clear that you’re hiking in a forest that overlooks a lake. The second photo lacks the feeling of being in a forest and looking out. A simple frame can change the image entirely.
The concept of framing is incredibly simple. The aspect that takes practice is implementing enough of a frame to add a distinct feeling to the photo, but not so much that the subject becomes unclear. In the series of photos with the cross - which are all the exact same photo, cropped three different ways - the frame changes the entire image. The first is a shrine that was carved into a rock wall in the forest long ago. The uncropped version is a photo of a rock wall into which somebody once carved a cross. The vertical version is a photo of an old cross in a rock. Too little of the frame won’t properly convey the mood. Too much of the frame won’t properly showcase the subject. Like all the other rules for landscape photography, this one is quite simple. The only difficulty is in studying and practicing effectively.
The vertical photo lacks depth and interest. The wide rock wall doesn’t have anything interesting going on in the sides of the frame, so it just makes the photo less clear. The final version retains enough of the rock formation to make it a nice frame but removes the plain rock from 2/3 of the photo. The framing emphasizes the subject of the picture while the crop removes the boring parts from the sides.