The use of wide angle lenses is very common in landscape photography. Wide angle lenses are mostly considered as lenses with a focal length of 24mm and wider for full frame DSLR’s or 18mm and wider for crop-sensor DSLR’s. Shooting with wide angle lenses has unique characteristics and great advantages which I will specify and explain in this article.
Short focal length lenses have a wide angle of view, meaning you can capture much of the scene you see. Different focal length lenses provide different field of view. The range starts from about 75 degrees (sideways) and goes all the way to 180 degress like in fisheye lenses. This ability to deliver an image with a wide angle of view allows you to capture an image which will include many details of the landscape you want to shoot.
Wide angle lenses create a perspective sense of depth and 3D. When shooting wide, objects which are relatively close to the camera will appear large and objects which are relatively far will appear very small. This exaggeration creates a sense of depth. The extreme size difference is created because of the distance ratio between the photographed objects and the camera. For example, lets say we take two identical cubes and place them 4 meters away from each other and shoot them at 14mm and then at 400mm while keeping the closest cube the same size in both shots – this is how it would look:
In order to make the closer cube appear the same size in both shots,you have to shoot it very closely at 14mm and quite far at 400mm. This creates different distance ratio between the cubes and the camera which leads to the exaggerated size difference between the two cubesand creates a sense of depth. Below is a photo of a small puddle shot the dead sea, Israel. I shot this image with a 15mm lens on a Canon 7D. Notice how large the “salt fingers” at the foreground look comparing to the ones after the small puddle. the ones close to me were about 30cm away and the ones after the puddle were about 1.5 meters away. You can see a great example of how it looks like here: http://i.imgur.com/D0Uos.gif
When shooting landscape images we usually want a large depth of field, meaning the whole frame, from foreground to background will be in focus and sharp. Depth of field depends on your focus distance, focal length and aperture size. When using short focal length (wide angle view) it is easier to achieve large depth of field. The wider you go, the easier you can achieve large depth of field, even in large aperture size. For example you can achieve the same depth of field at 15mm and F/8 or at 10mm and F/5.6 (this is just an example, not a true calculation).