How many watts of flash does a 20-square-meter studio need?

How much power the studio lamp uses has nothing to do with the indoor area, because the fundamental goal of the studio lamp is not to illuminate the room, but to illuminate the main body, so it has nothing to do with the room area. If you just take a standard photo, then a flash of 200WS is enough. If it is artistic photography, you know that photography is the art of running out of light. In addition to light distribution at various angles, sometimes light with different textures is needed, such as one-way soft light covered with grid cloth, soft light with point light source of beam bucket and colored light with color filter. This secondary treatment of light will lead to a lot of brightness loss of light, which requires a higher flash output index. Of course, a larger index is better for you to toss about various light distributions.