Split lighting is exactly as the name implies—it splits the face exactly into equal halves with one side being in the light, and the other in shadow. It is often used to create dramatic images.
To achieve split lighting, put the light source 90 degrees to the left or right of the subject, and possibly even slightly behind their head. Where you place the light in relation to the subject will depend on the person’s face. Watch how the light falls on them and adjust accordingly. In true split lighting, the eye on the shadow side of the face does pick up light in the eye only.
Loop lighting is made by creating a small shadow of the subjects noses on their cheeks. To create loop lighting, the light source must be slightly higher than eye level and about 30-45 degrees from the camera
In loop lighting the shadow of the nose and that of the cheek do NOT touch. Keep the shadow small and slightly downward pointing, but be aware of having your light source too high which will create odd shadows and cause loss of the catchlights. Loop light is probably the most common or popular lighting pattern as it is easy to create and flatters most people.
Rembrandt lighting is so named after the particular lighting style of the painter. Rembrandt lighting is identified by the triangle of light on the cheek. Unlike loop lighting where the shadow of the nose and cheek do not touch, in Rembrandt lighting they do meet which, creates that trapped little triangle of light in the middle.
To create Rembrandt lighting the subject must turn slightly away from the light. The light must be above the top of their head so that the shadow from their nose falls down towards the cheek (similar to that of Loop lighting). Not every person’s face is ideal for creating Rembrandt lighting. If they have high or prominent cheek bones it will probably work. If they have a small nose or flat bridge of the nose, it may be difficult to achieve.
Butterfly lighting is a portrait lighting pattern where the key light is placed above and directly centered with a subject's face. This creates a shadow under the nose that resembles a butterfly. It's also known as 'Paramount lighting,' named for classic Hollywood glamour photography.
Butterfly lighting is created by having the light source directly behind the camera and slightly above eye or head level of the subject (depends on the person). It is sometimes supplemented by placing a reflector directly under their chin, with the subject themselves even holding it
Broad lighting is not so much a particular pattern, but a style of lighting. Any of the following patterns of light can be either broad or short: loop, Rembrandt, split.
Short light is type of studio lighting setup where the face side which is further from the camera gets the main light. In this type of lighting setup, the side of the face which is toward the camera gets less light then the side facing away form the camera. It is often used for low key, or darker portraits. It puts more of the face in shadow, is more sculpting, and is slimming and flattering for most people.
Broad light is just the opposite of Short light. In the Broad Light setup, the side that is getting the most light is the side turning towards the camera. The reason this lighting style is referred to as “broad” is that it typically makes the face appear to be wider.
The side of the face that is towards the camera has the most light on it and the shadows are falling on the far side of the face, furthest from the camera. Simply put, broad lighting illuminates the largest part of the face showing.