The Beauty Dish is a very special light modifier, and my favorite key light (the main light) for portraits. It is a rigid, concave disc that has a reflector in the center. The interior surface is white or silver. I prefer white. That center reflector sends the light back into the dish and disperses it outward to the subject. The really important aspect of this light is that it is particularly flattering, particularly with younger subjects with fewer wrinkles. Used correctly, it provides light that enhances the beauty of the subject, hence the name “beauty dish”.
The beauty dish is typically positioned directly above the subject. In the natural environment light comes from above (the sun) so it looks right to our eyes to see this angle used in the studio as well. You’ll note that the dish is supported on a boom stand that allows the photographer to shoot directly at the subject without a light stand in the way. The stand makes it easy to adjust the angle and presentation of the dish. The other end of the boom has a weight (lead shot) that counterbalances the weight of the light.
The first picture of the beauty dish shows it with the dish exposed, and the picture to the right shows the beauty dish with a “sock” which is a diffuser that goes over the opening of the dish to soften the light. I generally keep a sock on my beauty dish.
The other crucial aspect to get soft light from the beauty dish is to position it close to the subject. The closer, the softer the light will be. As the light source gets farther away, it gives a harder look with more distinct shadows and highlights. 2-3′ is a good distance for the light from the subject. You can back up in a completely white studio with reflections of light coming from all directions, but keeping close to the subject is the general rule of thumb.
If you want to take better pictures but not purchase an entire studio worth of lighting, get yourself a beauty dish and a reflector. With those 2 items you can take shots that will substantially surpass the speedlight or built in flash on a camera.

Mounting the dish to a heavy duty boom lets it be positioned above the subject yet let the camera have direct access for the shot.
Finally a word about the center reflector in the beauty dish. The Elinchrom dish (and most other good brands) comes with several choices of reflector, such as gold, silver and white. I like to use the gold center, which gives a very slight warmth to the finished product. I think it is more like sunlight and imparts a more healthy glow.

This was taken with a beauty dish, giving flattering light. The dish makes a pretty catch light in her eyes.
The beauty dish is where I generally start in a photo shoot, and it is a great asset to the photographer. The round shape makes a lovely reflection, or catch light, in the model’s eyes, as seen in this shot taken with a beauty dish.