Rangefinder

Rangefinder cameras, as the very name itself suggests possesses a rangefinder and it is a mechanism which enables perfect focusing allowing the photographer to measure the correct focal distance and ensure that the photographs are never out of focus. In a majority of the rangefinder cameras it is found that two distinct images merge into one to produce the final perfect image. The present rangefinder cameras perform two functions together i.e. the focal length is adjusted in both the lens and the rangefinder with the help of a single control centre. The origin of the rangefinder cameras can be traced back in the pagers of history in the 19th century and at that time they were known as ‘telemeters’. However it was only in 2004 that digital technology began to be used in these rangefinder cameras. There are at present only three models of digital rangefinders available in the world and all of them are provided with interchangeable lenses. However these rangefinders are more expensive compared to the digital SLR cameras though they do not provide the live preview function on the LCD display.

Digital rangefinder cameras are found to have certain merits which pose it ahead of the digital SLR cameras. In the absence of the mirror, the wide angle lenses provide appropriate focusing. However it is to be remembered that most rangefinder cameras do not possess zoom facilities though there are exceptions which offer about three varieties of focal lengths to choose from.

It has often been alleged that the digital rangefinder cameras are often unable to prevent the parallax error as the photographer can see the viewfinder at a distance from the lens as a result of which the image may be imperfect. However, with the progress of time and the use of advanced technological tools, rangefinder cameras at present insert a brightline frame into the viewfinder which enables to check the parallax error.

DLP in flat screen projection televisions

One of the most prominent flat screen technologies used and released world wide apart from the liquid crystal displays or LCDs are the DLP or projection through digital light processing which are widely used in projection televisions which refer to those televisions having flat screen and those which employ video projectors for their functioning. This technological process was devised by Dr. Larry Hornbeck in 1987 for use in the video projectors and it was registered as a product exclusively copyrighted by the Texas Instruments. The image is produced by the digital light processing technology with the help of the Digital Micromirror Device or the DMD and it is integral to the functioning of the DLP projector. The matrix of the semiconductor chip is composed of tiny microscopic mirrors and these comprise what is known as the Digital Micromirror device. In the flat projection screens of the digital light processing projectors these microscopic mirrors help in the projection of the image where each mirror represents different pixels which of course combine to form the final image on the projector screen. In case of the usage of the DLP technology there are three prominent means by which the colored images are produced and projected in the flat screen displays.

In some of the projectors it is found that only a single DLP chip is used and in these cases it can be observed that the projectors spin the color schemes in the wheels of a spinning color wheel which is located in between the lamp and the digital micromirror device. This color wheel is made up of the three primary colors visible to the human eye i.e. red, green and blue. There is also the ‘rainbow effect’ which is observed in some of the DLP single chip projectors which at times cause side effects like headaches to the audience. Three chip projectors having DLP technology emit color through the lens after having split the rays via a prism.

Advantages of digital cameras

Cameras have been one of the most significant innovations of the times and they are extremely important as they enable human being to record or capture such memories which not only last them a lifetime but are often great companions in solitude serving as reminiscences of wonderful memories of the past and at times they serve as recollections of thing s that no more exist. Therefore, cameras are the only tools that can record live memories and initially the analog cameras wee prevalent. But soon with the progress of time and scientific development, digital technology developed considerably and digital cameras came into use. Digital cameras are not only easy to operate, moreover, they perform multifarious functions and the picture quality is definitely more enhanced because of the use of digital technology.

A very significant advantage of digital cameras is the fact that it is possible to view the captured image immediately and in case the photographer is not satisfied with the image, he can re-shoot the image again by deleting the previous one. Digital camera photos can be retrieved easily by transferring them into a computer within its storage device by means of a USB port.

Moreover these photos can also be viewed in television screens. Therefore, all digital photos do not require printing like analog versions and they can also be sent, viewed or shred through the internet. Unlike the photographic films which were used in analogue cameras, they had a fixed capacity and only a stipulated number of photographs could be taken with the help of these. However digital cameras offer far greater options in terms of numbers and some cameras provide memory expansion functions too by means of inserting memory cards. Moreover, editing is also possible when it comes to digital camera images and various computer software functions are available at present to alter the images accordingly.