Cold light source three primary colors soft light is following the incandescent, halogen and other products after the light source. As the cold light source is generated in the electric field under the action of electronic collision excitation fluorescent material and light, no infrared light and halogen light generated by the infrared radiation heat, so the basic does not produce heat, it is called "green energy saving lamp" , Especially for the production of television news programs. Its advantages are soft light, clear, no obvious spots and shadow, a better reproduction of the natural light projection effect. For standard definition and high-definition cameras, the color temperature of 3 200 K is a typical lighting-type lighting, and there is a wide range of light and uniform illumination and other characteristics.
Therefore, the picture taken out of the clean, deep and natural clear, than with the traditional film and television lamps direct shooting of the screen is more intuitive for the TV program recording provides the ideal performance space and scene effects, cold light source three primary colors soft light Also became todays television news studio one of the most commonly used lamps.
Compared with the method of light-emitting light only, the advantages of the three-color soft light of the cold light source are as follows: First, the light source is stable, the flicker-free phenomenon, the color temperature standard and the color reduction rate are high; , Color rendering, color rendering index Ra up to 90 or more, and the basic does not produce heat, greatly improving the news studio ambient temperature, so that the host, announcer from sweat, dry mouth, for the The studio for a long time live work to create a more favorable work space; Third, under the same illumination, the electricity consumption is only 1/8 of the halogen, energy-saving effect is obvious; Fourth, the lamp life Long, can reach 10000 h or so. These are the general advantages of its universal application for news studios, and the parameters are in full compliance with the studios shooting requirements. News studio lighting system configuration diagram shown in Figure 1.
Figure 1 News studio lighting system configuration diagram (dimming console + dimming cabinet + lighting system)
1 cold light source three basic color soft light basic application
In the news studio, usually with two cameras to shoot, a viewfinder for the panoramic view, a viewfinder for close-range. Figure 2 shows the layout of a news studio. The scope of the cloth should be centered on the host / announcer, consisting of five cold light sources with three primary colors, and two of them are dominated by two tubes. Main light front
And the host of the horizontal distance of 3m, the vertical height is 3m, just 45 ° angle. 3 sets of 2 tube lights for the auxiliary light, the height can be parallel with the host or slightly higher face.Figure 2 a news studio light when the dimming circuit in 100%, to meet the illumination at 1500lx, color temperature maintained at 3 200 K, we will find the characters and scenes lack of layering, the picture is more dull. This is because the light is too small. Therefore, the use of dimmer control light ratio of the way to fine-tune, that is, the principle of three-point light distribution, so that the main light, backlight and auxiliary light to form a certain light than the authors experience is 1: 2: 0.5) The main light chooseion dimming range to 100%, auxiliary light chooseion dimming range of 50% to 75%. Which is the specific light of the arrangement also pay attention to the main light is generally slightly on the left side of the host 15 ° ~ 25 °, the angle of the characters and lamps at 45 ° or so. Backlight can choose 2 1 kW spotlight or the same amount of 2 kWLED spotlight, the dimming range can be 100%. But also in the hosts head above the left side of the face of the external position plus a 4 tube cold light source as a secondary light, attention should be consistent with the main light position, which is usually said that the basic light. Its advantage is that it can increase the average illuminance of the characters in the area being photographed, and the localized subtle changes of the characters can meet the basic requirements of the cameras light to the characters and constitute the whole picture and the local picture level. Is to highlight the character characteristics of another cloth method. 2 light cover the use of skills Tips: cold light source three primary colors soft tube 6, 4 tube lamp embedded with a rotating and reflective of the four pieces of cover, cleverly move the angle of the cover, the use of cover reflex projection angle changes, The reflected light can be mapped as auxiliary light to the face of the subject, thereby assisting in enhancing the illuminance of the face light. Different broadcast moderators skin color is usually a slight difference, especially the male and female hosts skin color are generally some obvious differences, the use of light to cover the light reflected as the face of auxiliary light cloth light, not only highlights the characters face Expression, but also with the background screen to form a subtle change in contrast, and make the overall picture more than some sense of hierarchy, for the addition of human facial light local deficiencies played a significant effect. Method 2: the host in the backlight light, the general use of two 1kW spotlight. Spotlight also has two can move the cover, in order to highlight the outline of the characters effect, can be used to set a specific head of the brain after the brain, that is, the spotlight from the upper and lower cover closed to the shoulder above the scope of projection, characters and lighting angle At about 60 °. Another spotlight is specifically aimed at the shoulder below the body projection. Likewise, the two movable shelters of the spotlight can be used to close the cloth. Use light to focus on the method, highlight and strengthen the outline of the characters. This camera is used to explain the composition of the characters and scenes between the three-dimensional will become particularly clear. Soft facial expression, the outline of the characters and the background screen can form a certain level and depth of field, so that the overall picture coordination, natural.