[ SIGMA Macro Macro Ring product photo ]
Flash of English, called Flash Light. Flash is one of the ways to enhance exposure, especially in dark places, playing flash help make brighter scenes. Drawbacks of using the flash will appear, for example, people in the film, the flash of light, the pupil of the eye may occur in the residual phenomenon, and then place "red eye" scenario, many camera companies will "eliminate red-eye," this feature on the design, before opening play in a weak flash of light to the pupil to adapt to, and then the implementation of a real flash to avoid red-eye occurs. Middle and low digital cameras generally have three kinds of flash modes, namely automatic flash, red-eye reduction and flash. High point of the product and then also provide a "force flash" or even "slow flash" feature. Second, the role of flash: The role of flash in low light situations Pishezhuti, flash light Pishezhuti to obtain the correct exposure. Flash their target is "flash index" flash flash index is the luminous intensity, reflected in the use of conditions in ISO100, flash index divided by the actual shooting of the lens aperture value is the scope of the flash can illuminate . Third, the type of flash: In actual use, we often come into contact with is the "airborne flash" and "stand-alone external flash," a large number of studio flash with our later description. Here we talk about the difference between the two lights and the camera for attention. 1. On-board flash: Start by talking about "on-board flash." As the name suggests, "on-board flash" the camera body is built, equipped and powered by the body and can not separate the flash and body. The most common is to fool the camera in the upper left or upper right corner of the general (some are automatically jump out), shining the guy in the top of the modern SLR pentaprism commonly known as "machine dome" is also it that though it is small, sometimes can not really missing it. "On-board flash" feature is the use of flexibility, volume and index are small, flash index of more than 9 to 14, from the lens of more recent, relatively few functions. I do not need flexible believe we all understand. Index of small-is "on-board flash" fatal determined that it can only act as supporting roles. The fool the camera, the lens aperture is usually small, only a handful of high-grade fixed focus cameras with maximum aperture is about 2.4 ~ 2.8. Most of the wide-angle zoom cameras with paragraph 3.5 maximum aperture is only 4.5, in the telephoto end of only 9 to 11 individual 140mm telephoto end than at the maximum aperture cameras with only 13. We can easily calculate the film ISO100 when using wide-angle radiation section of the effective distance is 3 meters long or more paragraphs only 1 meter. I often see many friends in the photograph using the camera fool, especially when the collective commemorative photos from Beishezhuti far, far more than the "on-board flash," the effective exposure range, which is an annual National Day, all to steal Beijing store wash out a lot of exposure a serious shortage of reasons for the black pieces. Said, "Airborne flash" from the lens of more recent, I believe we all see a fool's built-in flash on the camera lens next, even SLR's "machine top light" to "jump up", is still far from the lens . Now I say "relatively close distance of the lens" refers to the optical axis and the camera flash light-emitting optical axis of the lens too close, if at night taking pictures, they will form ugly "red-eye." Mentioned that, had referred to "eliminate red-eye," this function. "On-board flash" has a unique feature is the "red-eye removal." "Red Eye" phenomenon is due to the lens axis and axis flash too close, in a very dark time of the corresponding human pupil larger, flash flash photo in the fundus through the pupil, the microvascular dense Reference in the light reveals bright red under formed the annoying "red eye", "eliminate red-eye" is the official launch of Flash flash before shooting start with a small flash, people's eyes, miosis, reduce "red eye" phenomenon. The "stand-alone external flash," as the top frame in the camera, flash camera optical axis and optical axis angle very, very high, will not form a so-called "red eye" phenomenon. A friend had asked how a very advanced flash did not "eliminate red-eye" feature, it is because - no need to. "On-board flash," Due to various constraints, functions have been incomplete. Although in some high-end SLR cameras of the "on-board flash" feature is also very diverse, able to Rear Curtain Sync, surrounded flash exposure, flash exposure compensation, and even flash index also changes with the lens focal length of 14 ~ 20 automatically change, and change the flash coverage, respectively, to cover 24mm ~ 85mm. But with high-grade "stand-alone external flash" than poor enough. Stand-alone external flash: Finished the "airborne flash" another look "stand-alone external flash." Most of these flash produced, high-index, all fully functional. Because the flash index size can be divided into two classes: the index of 35 or so flash, except not about "shaking his head", the function and index of about 55 is almost the same, but only the latter price about 1 / 2. "Stand-alone external flash" comes with the battery compartment, an independent power supply, in addition to conventional pre-connected, Rear Curtain Sync, Slow shutter sync, surrounded flash exposure, flash exposure compensation, manual flash, multi-grade light than the flash, AF assist lamp and other conventional features, a large lamp lights up and down activities of more than 100 degrees, turning left more than 270 degrees, shooting pictures of people in the room can be free to light down the wall or ceiling, with the reflected light illuminates Pishezhuti, Photos appear natural, no shadow. Some light can achieve all the shutter speed flash sync, especially for shooting outdoors in strong light, backlit photos of people to face when the fill light. Strobe function is "headlamps," one of the interesting features, in a very dark background with a strobe flash before photographs could be a series of still images, very interesting. And partly with the onboard flash can flash or another flash light source remote to do more than split flash, easy to professional studio effects, this feature first appeared in MINOLTA3500xi5400xi and 5400HS, the later the transfer of technology to a Canon, the latest in Canon top flash 550EX also realize this function. In summary, flash photography in the annex is an integral member of both agile and light the "on-board flash" or the versatile "independent-type external flash", the correct use can give it to bring your photographic life more fun and wider world.