In order for the single lens reflex to work, mirrors are used within the camera to direct light from the lens to the back of the camera and the viewfinder. An SLR digital camera is one that uses a single-lens reflex and does not use film but stores the pictures as digital or image files.The first digital camera was made by Kodak in 1975, with the first SLR model created by Sony in 1981. The basics include a mirror that reflects light in a 90 degree angle from the optical lense to the view finder. This light is then reflected three times so the person can see the image properly. When the picture button is pressed the mirror swings in an upward motion which causes the aperture to become smaller. The shutter opens and then light touches the image sensor. A 2nd mirror will swing over the image sensor which will end the light exposure and the mirror swings back into place. In this period there is no image through the viewfinder, known as viewfinder blackout. This entire motion happens very quickly with SLR cameras, as this motion can occur as much as 10 times in a second.
The depth of field refers to the distance between the farthest and nearest object in the picture. These cameras also allow for accurate viewing of depth of field and the lenses can be interchanged. The reason digital SLR cameras are preferred by professionals are that the photographer has a very accurate preview of the actual picture that is being taken. The mirrors used in the camera can be either penta prismor penta-mirror. Entry level versions typically use a penta-mirror, which is a prism that has 5 sides. Instead of being made of glass the penta-mirror is made plastic which is less expensive and much lighter than pentaprism. The pentaprism is in the same shape as the penta-mirror but it is made of glass. When light passes into the prism it bounces off the back wall, changing light direction by 90 degrees.
The ability to change optical lense will depend on the camera maker and the type of lens. The lenses must have the same shape so that it fits into the lens mount on the camera. Many manufacturers use lenses that can fit in many cameras while some manufactures make lenses that are proprietary in which case will only fit in that manufactures camera. The proprietary nature of some SLR digital camera manufacturers would be one of the main reasons that once a photographer makes a choice in a particular camera he stays with that brand as all of their lens will only work with that brand.
WTS Photonics Co., Ltd provide our customers with the superior quality optics products and precision Laser Optics products ,serves a global markets including Laser, Electronics, elecommunication,Thermal Imaging, Infrared Sensor for Industrial, Medical and Scientific Research applications. We spacialize in bandpass optical filters,laser line filters,Optical Lenses,meniscus lenses, beam splitters , sapphire windows, Mirrors, Filters,Precision Prisms, penta prisms, Quartz, MgF2, CaF2, Ge, Silicon etc..More information about our products pls link to our official website: www.wtsphotonics.com.
2011年9月8日星期四
2011年8月1日星期一
Get Discount Meniscus Lenses Online
Are you planning to save money on your necessary items i.e. on your meniscus lenses? Now,it is the time to pay your attention to discount lenses. You can shop online, as now-a-days; it is the best available medium of purchasing. With the availability of the Internet at almost everybody's house, the shopping medium has become easier and cheaper. One can easily get discount contact lenses online, without scouting over the high street for a single pair of such kind of stuff. Now everybody becoming tech savvy, they are relying on the online service for accomplishing every single work.
Even people, who do not have any sight problems are clinging towards such kind of eye wears, as these are also used for fashion and style. In today scenario, the demand of the discount meniscus lenses has scaled heights and this is the reason the related brands are on a high these days. These people usually go for colored ones, in order to give an extra zing to their personality. Today generation who understands the definition of funk and punk in a broader manner is keen on fetching such kind of colored eye wears in order to make them look special while going for proms and discs.
Considering the growing demand, the related brands have now launched discount contact meniscus lenses and these are now a hit mostly among the young crowd.A tattooed skin, a pierced body with a colored sight makes them stand out in the crowd and so they are mad for such kind of stuffs. One can just go online and can surf various websites and can compare the prices and can even check out if any outlet is offering any kind of special offer. But before going for any kind of discount lenses, its mandatory to fetch an optician and should approach under his advice.
WTS Photonics Co., Ltd provide our customers with the superior quality optics products and precision Laser Optics products ,serves a global markets including Laser, Electronics, elecommunication,Thermal Imaging, Infrared Sensor for Industrial, Medical and Scientific Research applications. We spacialize in bandpass optical filters,laser line filters,Optical Lenses,meniscus lenses, beam splitters , sapphire windows, Mirrors, Filters,Precision Prisms, penta prisms, Quartz, MgF2, CaF2, Ge, Silicon etc..More information about our products pls link to our official website: www.wtsphotonics.com.
订阅:
博文 (Atom)