https://www.youtube.com/watch?v=T4u_92uRsWc 

Lighting 101: 3-Point Lighting

  For this setup you will need:Key Light -  The Key Light defines the most visible lighting and shadows on the subject and acts as the primary source of illumination.  You can use just about any light source as your Key Light, whether it be the sun, a window, a lamp, or a video/photography light. For this video, we’ll be working entirely with constant lights for portrait lighting. Fill Light - The Fill Light softens and extends the illumination provided by the Key Light, making the subject more visible and softening the harsh contrast and dark shadows cast by the Key Light. Your Fill Light can simulate natural light from the sky, or secondary light sources such as a table lamp. A lamp or video light can be used, or one can use a reflector to do this as well.Rim Light - The Rim Light creates a bright line around the edge of the subject, to help visually separate the subject from the background and bring them further into the foreground of the photo. This too could be a carefully positioned reflector or another light source.Let’s get started:Step 1: You will want to set up or turn on a work light to establish your subject and frame. Bear in mind, this setup can be completed within 15 minutes but can take up to half an hour or longer depending how much adjusting you do, so you’ll want to make sure your subject is comfortable before you begin or use a stand in for practice until your talent arrives. Once you have your subject and frame established, you want to block off any natural light in the room that will add a glow or ambient light to the room.Step 2: Now we’ll set up our Key Light. You will want to position your Key Light 15-45 degrees to the right or left of your camera, to illuminate your subject. This will create a strong contrast between the light on the near side of your subject, and the dark shadows on the far side of your subject (away from your Key Light). You will want to elevate your Key Light a foot or two above the height of your subject, until you just begin to see a Rembrandt Lighting pattern (link to video/show short clip of the pattern). Your Key Light should be your brightest and strongest lighting source, and the additional lights will work to soften and shape the base light from the Key Source.Step 3: Next, we’ll add in the Fill Light. This is the point where you’ll begin to shape the light on your subject. The position of the Fill Light will be 15-45 degrees to the side of your camera, opposite the placement of your Key Light. So, if we placed the Key Light on the right side of the camera, our fill will come from the left side. Your Fill Light will be about half as bright as your Key Light, to soften the shadows cast by the Key source, without beginning to cast shadows of it’s own, which will often look unnatural and draw attention away from the subject.The Fill Light may be raised to the subject’s height, but should remain lower than the Key Light. Adjust the height of the Fill to see what appeals to you aesthetically. Alternatively, you can also bring in a reflector or bounce to act as your Fill Light, reflecting light from the Key Light back onto the subject to fill in the darker shadows.Step 4: Lastly, we’ll bring in our Rim Light. The Rim Light will be placed behind your subject, across from the camera, just off frame, and raised above the subject at level with the Key Light. Adjust the Rim Light to give you a bright outline, highlighting the top or side edge of your subject. The intensity of your Rim Light can be as bright as necessary to achieve the intensity of the highlight you want around the edge of your subject. The positioning of your Rim Light and the focus of light behind your subject is key, to ensure the light falls only on the subject and does not illuminate the background. You want to keep your background darker, so the Rim Light around the edge of your subject pulls the subject forward and away from the background.And that’s it. Three Point Lighting can be a great starting point for lighting just about any subject, person or otherwise. With this basic setup, you can adjust the height, positioning, intensity and source of lights to create your own look and feel for any lighting setup. For a darker, moody look, pull back the intensity of the fill to give the shadows a darker contrast. For a mysterious look, focus on backlighting your subject, and lower the intensity of your Key and Fill Lights. There are many options for you to customize the look and feel of each setup you want, but don’t feel like you have to have professional lights at your disposal to accomplish the looks you want. This setup can be implemented with basic table lamps, or even outdoors using the sun and a reflector.