How to shoot a total solar eclipse with a mobile phone or digital camera? Come on, everybody, 3Q.

The simplest method of celestial photography is to shoot directly with the camera! For the sun, many cameras can take big pictures at the telephoto end, so in the non-total eclipse stage, we only need to cover the filter in front of the camera lens to take pictures easily. If you use the ink basin method or telescope projection method to observe the solar eclipse, just take pictures of what you see. As for the total solar eclipse stage, just use the camera to shoot at the sun. Data: Preparations for shooting the solar eclipse with ordinary digital cameras July 22nd this year was a once-in-a-lifetime total solar eclipse. Friends who don't have professional equipment can use ordinary digital cameras to keep this rare souvenir. In order to take better photos, adequate preparation is essential. The camera I used is an old Kodak camera with 74.304 million pixels, with a focal length of 34- 102 mm, 3-light and 4-digit zoom, and no manual function. 1, lens filter 1 filter is essential. A friend said that a camera with manual function can control low sensitivity, small aperture and high speed exposure without a filter. I think this method is not desirable. The sun is very strong. Even if you don't take pictures, it's easy to damage the camera if the lens is facing the sun directly! Filters must be used to block most sunlight to ensure safety. ② There are two kinds of lens filters: plastic and glass. Plastic film used to be a photographic negative, but now it's hard to find it. I used medical x-rays, and I chose the one with colorless film base. Glass materials are easily available as welded filters. You can buy it in the hardware and electrical accessories store. The price of the electric welding filter I bought in Shenyang is 1 yuan (retail price) for your reference. The advantage of glass filter is that the transmitted sunlight is basically parallel light, so the captured sunlight has high definition. The disadvantage is that the welding piece is dark green instead of black, and the photo taken is green with large color difference. The plastic sheet will spread to a certain extent, which will reduce the clarity of the photo. The advantage is small color difference. (3) Lens filter transmittance The welding pads I can buy here range from No.7 (lightest) to No.0/2 (deepest). A friend said that the lightest welding is enough, but I found that the darkest welding is not enough! Obviously, we should have an objective standard to choose the transmittance of the filter. Open Shoot's photos with potoshop and look at their "histogram". Figure 1 is the sun shot with the "8+8" filter, figure 2 is its histogram, figure 3 is the sun shot with the "12" filter, figure 4 is its histogram, figure 5 is the sun shot with the "4X" filter, figure 6 is its histogram, figure 7 is the sun shot with the "3X" filter, and figure 4 is its histogram. "12" filter means 12 welded plate; A "4X" filter means that four X-rays overlap. The first is completely exposed pure black, the second is Zhang Shen gray, the third is light gray, and the fourth is unexposed; The "3X" filter is the "4X" mentioned above, and the fourth filter is unexposed. The dense part on the left side of the histogram is the sky; Some vertical lines on the right are the brightness of the sun. The brightness line representing the sun in Figures 2 and 6 is not close to the right line of the histogram, which is a relatively "normal" exposure. In Figures 4 and 8, the vertical line representing the sun is close to the right line of the histogram, which actually exceeds the range of the histogram, indicating overexposure. But from the photo, the "normal" exposure looks a bit like the moon, lacking the bright and dazzling feeling that the sun should have. I think overexposure is more appropriate. In fact, compared with Figure 6, Figure 8 only lacks an unexposed "transparent" X-ray, but the effect is quite different. The color difference between the photo 1 and the pad in Figure 3 is unpleasant. After comprehensive comparison and many experiments, I finally recommend 3X film, which is a slight overexposure filter composed of X-rays. If everyone's X-ray density is right, "2X" will definitely be better than my "3X". In order to ensure success, friends are advised to visit and shoot more times. There may be some differences between different cameras, and the transmittance of X-rays cannot be quantified. (4) Lens filter sleeve For convenience, I made a sleeve of paper and put it on the lens, and a piece of cut 3X paper was stuck on the sleeve. This is not only convenient to use, but also can prevent scattered light nearby. 2. If the paraxial viewfinder filter is not a SLR viewfinder, you should also add a filter, and its light transmittance can ensure that you don't look dazzling. Of course, it is more convenient to use plastic sheets. I used the completely sensitive black part of the medical X-ray, cut a small piece and stuck it on the camera to cover the viewfinder. 3. Focal length In order to make the sun as big as possible, the maximum focal length must be used. My camera has 3x optical zoom and 4x digital zoom. Some friends think digital zoom is useless. I did a comparative experiment: the text in the newspaper was shot with 3x optical zoom and 4x digital zoom. The contrast was only optical zoom and PS zoom, or the former was clearer. So I think we should make full use of digital zoom instead of rejecting it. According to this focal length, the diameter of the sun is about110 of the photo length. Figures 1, 3, 5 and 7 all take the whole uncut photo directly. 4. The shooting mode is landscape (distant view) mode, and the flash is turned off. 5. The tripod has used 3x optical zoom and 4x digital zoom, and the focal length is equivalent to more than 400 mm! Handheld cameras are prone to shake, which makes the surrounding sunlight blurred or distorted. A tripod should be used. Friends who don't have a tripod can put their cameras near corners, colonnades, railings and other places. In order to reduce the shaking, but avoid the lamp post, because the light may be on during the solar eclipse! 6, date and time calibration In order to leave an accurate time in the photo, we should pay attention to the time of calibrating the digital camera. Based on the standard time of the National Astronomical Website National Time Service Center, the website is:/The specific operation method is: adjust the time of the digital camera to one or two minutes after the current time, and when the standard time reaches this time, press the "OK" button to start synchronization. The time error of the calibrated digital camera should be within 0.65438 0 seconds. The last calibration should be carried out on the evening of July 2 1. Of course, your watch should also be calibrated to accurately grasp the eclipse time. 7. Enough batteries. Needless to say, the battery is enough. 8. What else can I see? Watching the total solar eclipse is not only about the changes in the sun garden, but also something worth seeing: ① Bailey beads: like a beautiful diamond ring, you can only see them at the beginning and end of the total solar eclipse. ② Mercury: Mercury that many people have never seen. On the east side of the sun, the area of total solar eclipse may be photographed. Don't miss it! Venus, Mars, Jupiter and the brightest star Sirius are also in the sky.