Stroboscopic LCD screen

The LCD screen also flashes frequently. After all, it is charged. The optimal refresh frequency of each LCD is different. Just set it to the one that is most comfortable for your eyes. Although it is different from CRT in principle, there is a backlight board in the middle, and the high voltage of the backlight board will cause stroboscopic.

What is stroboscopic photography?

Flash strobe photography, also known as continuous flash photography, records the continuous motion process of moving objects on the screen with the help of continuous flash of electronic flash. Stroboscopic photography is generally divided into two types from the equipment: one is shooting with automatic frequency electronic flash (referred to as electronic strong spot); The second is to shoot with an ordinary flash. Because of the different shooting tools and methods, stroboscopic photos have their own characteristics. Let's first take a look at the method of taking stroboscopic photos with electronic strong points. Electronic spot is a new type of photographic lighting equipment. When it is fully charged, it can blink as frequently as a pistol. The flashing frequency of the high-frequency electronic stick can be adjusted as required. The higher the flash frequency, the more exposure times of the film, and the more images appear in the photo. Generally speaking, this kind of lamp can flash dozens or even hundreds of times per second. When shooting a moving object with an electronic support point, dozens of overlapping and patched images can be left on the screen. These images generated every once in a while can give people a strong visual feeling of rhythm, which can make people feel novel, because the visual effect of freezing the scene on a high-speed frequency screen is invisible to the naked eye. When taking stroboscopic photos with electronic strong spots, you should choose a black background, and the subject should be as far away from the background as possible to avoid stroboscopic lights illuminating the background, thus affecting the effect of the subject. If the subject is close to the background, it is best to make the flashlight and the subject form the illumination angle of side light and side backlight, and the subject also has obvious contour lines to prevent the image from being mixed with the background color. If there is no strobe, you can use the following techniques to take stroboscopic photos: first, take stroboscopic photos with a group of light sources composed of multiple strobes. Because the shooting interval of flash group can't be very close, only a few complete and clear images can be taken by continuous flash with ordinary flash group, and the images generally don't overlap each other, so the sense of movement and rhythm is poor. When shooting, we must first determine what kind of images to leave on the screen, how far apart the images are, whether the images should be connected by virtual shadows, and so on. , and then decide the position and quantity of the flash. Secondly, choose a dark background first. It is usually better to shoot at night with a low angle and a dark sky as the background, or find a spacious room to ensure that the images of moving objects are not disturbed. In addition, in order to make the picture clean and the main body stand out, it is best to turn off all other light sources except the flash for main lighting. In order to let people know the direction of movement, a small number of very dark lights can be placed on the scene, and the light source should be as close to the ground as possible, with a reverse light irradiation angle with the disturbed object. When shooting formally, open the B door of the camera, release the lock with the cable, make the shutter of the camera open, and then let the moving body start to move. The photographer controls the flash by hand and flashes one by one according to the different movement postures of the moving body. If you need to take three shots, flash three times with three flashlights; You need to take six images, which can be flashed twice with three flash lights or six times with six flash lights. It is best to find multiple assistants to operate flash separately. After reaching a tacit understanding, the effect is also very ideal. If the motion speed of the moving object is slow and the motion process is long, then a single ordinary flash can be used to shoot. This stroboscopic method is to fully charge the flash, lock the camera door B, let the flash flash at the moment when the moving body starts to move, and record the first image; When entering the next shape, flash again and record the second image; In this way, after a photo passes through multiflash, it will leave a number of moving human images with different postures. How to master the exposure of stroboscopic photography? If several images are separated from each other, the exposure is calculated according to the usual single lamp flash. If several images are closely connected and partially overlapped, the exposure of these images will increase with the increase of flash times. Therefore, when overlapping flashes, the exposure should be reduced by 1-2 aperture. In order to provide a larger range of motion for the moving body and facilitate the recording of the movements of the moving body at various stages, it is best to use a wide-angle lens when shooting. In order to be more sure, it is best to conduct several experiments before shooting, so that the moving body or character can practice several times more within a certain shooting range, so that the two sides can cooperate with each other and the shooting can be sure.