A piece of fingernail-sized film can store an A4 paper-sized file content; a roll of 16-mm film can store 2,700 pages of files, equivalent to two woodcut "Dream of Red Mansions" ancient books... Microfilm technology is not a new technology. It has a history of 180 years, which is to use traditional photography to film files on film. The process of microfilming must first be to split the file into a single page, and write the serial number. The technician responsible for filming adjusts the focal length, aperture, and light of the suspended 16mm camera on the camera, and then flattens the page. Put it on the photo stage and complete a one-page archive in about 2 seconds. Each machine can complete 5,400 pages of files per day, that is, two rolls of film (15 meters per roll). After the shooting, the film is developed, fixed, washed, and copied to complete the entire production process. Unlike general cameras, microfilm cameras, film, and consumables are imported and have high resolution, high resolution, and high contrast. For example, a file equivalent to A4 paper size, after shrinking 25 times on 16mm film, has an area of ​​1 square centimeter, which is equivalent to a fingernail size. "Large" files such as maps and engineering drawings are produced with a 35mm large machine. Four kinds of microfilm specifications, such as 16mm, 35mm, flat film and window opening, which are commonly used in the world, can be made here. In the mid-1970s, China introduced microfilm technology, which was first used in the National Archives and the Palace Museum. After the completion of the micro-center of the Provincial Archives in 1982, the archives of the Republic of China, the archives of revolutionary historical data, and the archives of the documents after the founding of the People's Republic of China were filmed into microfilm, accounting for more than 20% of the total inventory files. In addition, it has produced more than 9 million microfilms for archives in Nanjing, Suzhou, Wuxi and other cities. At present, due to factors such as high production cost and long cycle, the micro-files are not widely used, and there are not many users. Similarly, a volume of paper is produced, and the paper and film costs are three or four times different. Some people think that it is not worthwhile. In fact, from the perspective of the life cycle of file storage, the cost of the two is similar, mainly a consciousness issue. The US Archives Law expressly stipulates that all historical and precious files must use microfilm technology, and more than 30% of ordinary files use microfilm technology. Fortunately, the National Archives Bureau has taken the proportion of micro-files as a hard bar and included it in the evaluation and evaluation of the archives in the future. In recent years, the center has also introduced internationally advanced color film microfilm technology to process some of the precious archives in the collection, leaving the historical features to future generations. You can draw on the face and sew according to the drawing lines.You can also send us the picture,and we can sew the face for you. New Toy Baby Dolls,Toy Baby Dolls,Rainbow Dolls,Barbie Princess Dolls Nantong Einsame Familie Toy Technology Co.,Ltd , https://www.nteinsamefamilies.com