In recent years, with the continuous development of LED module development technology, the lighting design and use of LED lamps in studios have become more and more common, and TV studios that completely adopt LED lighting have appeared. It can be seen that LED lamps, as a new type of green and environmentally friendly lamps, are leading the development direction of the industry. So what are the details of the use of LED panel lights?
Color Temperature Adjustment
At present, there are a lot of flat light products on the market, and each manufacturer's flat light has different characteristics. There are two ways to choose the color temperature of lamps and lanterns. One is the variable color temperature lamp type, which uses the brightness ratio of the low color temperature and high color temperature LED modules to adjust the color temperature. The advantage is that the color temperature is more accurate and easy to use; the disadvantage is that if the color temperature is adjusted to a higher or lower level, only one-half of the LED module of the lamp is in use, and the brightness is low. The other is a constant color temperature lamp type. Mostly 3200 K or 5600 K.
However, due to the uneven technical level of manufacturers, the quality of LED modules is also different. The actual measurement index of color temperature and the nominal index often have a color temperature difference of about 100 K～150 K. In actual use, the accuracy of the color temperature affects the matching of cameras, large screens and other devices, and directly affects the presentation of the picture. If the color temperature of the lamp has a large deviation, you can use Leyden color paper to solve it. Assuming that the color temperature of the large screen is 5800 K, and the color temperature of the lamp is 5000 K, you only need to add 80 color paper in front of the lamp to increase the color temperature to 5800 K to match the large screen. If the color temperature of the lamp is higher than the color temperature of the large screen, use Leyden 85. It should be noted that any type of colored paper has an impact on the color rendering index of the lamp. Therefore, in the selection of flat-panel lamps, pre-tests are used to select LED flat-panel products with relatively accurate color temperature.
Projection Angle
The better projection angle of LED flat light as surface light is 40°～45°. Many small domestic studios have a floor height of less than 5 m, and depending on the situation, the projection angle is often smaller. Generally speaking, the larger the projection angle, the better the three-dimensional sense of the surface light, the larger the shadow area of the face, and the less stray light of the surface light. The smaller the camera angle, the worse the three-dimensional effect of the surface light, the smaller the shadow area of the face, and the easier the stray light is on the background.
Cloth Illuminance
The standard of studio surface illuminance is uncertain on a global scale. News studios in Europe and the United States often use low illumination of around 300 lx, with a large aperture of 2.8 to 3.0 for the camera, to obtain a picture effect with a large background blur and depth of field. The surface illumination of CCTV news programs reaches 1000 lx to 1500 lx, and the camera aperture is about 5.6, which gives a clear background picture effect. The advantage of high illuminance is that the details of the character's skin and clothes are more easily reflected.
With the development of technology, the latitude of cameras is improving, and the efficacy of flat panel lights is also improving. The two processing methods of high and low illumination are more based on the needs of subjective artistic effects. Use the LED panel light to distribute the light. The ratio of the illuminance of the face light to the backlight illuminance is usually 1:1.5, and the ratio of the illuminance of the face to the background (large screen) illuminance is 3:1. The light ratio should also be adjusted according to the specific situation.
Shadow Processing
The shadow of the host’s face has always been the primary focus of the lighting engineer. The main means to reduce shadows are:
Add soft light film to make the light quality softer;
Use multiple flat lights to influence each other to dilute the shadows;
Reduce the projection angle of the surface light;
Add eye lights to supplement the light on the host’s eye bags, chin, and neck to dilute the shadows.
