Light and depth of fieldWritten by Jakob Jelling
By Jakob Jelling http://www.snapjunky.comWith such a fantastic device as digital camera for recreation of magic in arts, a lot of care needs to be taken so as to maintain perfection of end product. This perfection is not only obtained by artistic feeling of photographer but also with intricate knowledge of every minute aspect of medium of creation of art (in this case digital camera). And these minute aspects play a vast role in defining ultimate perfection. The digital camera, light and depth of field are one such factor that would come into light in this subsequent discussion. Basically, depth of field is a measurement of acceptable sharpness. Yet this is very strictly a personal preference, and varies from person to person. Thus to be more formal, depth of field can be defined as area inside an image that demonstrates an ample sharpness that can be considered more or less in focus. So depth of field is range of distance, measured along lens axis, as per which image is caused to be sufficiently well and sharp in photograph. The rest is as follows! The depth of field defines zone where all elements show clearly from foreground to background. Three factors control depth of field in an image, they are distance of subject, focal length, and aperture used to capture photograph. For people using compact digital cameras, one of subjects of out of ordinary interest is depth of field because depth of field is more easily said than done to control with a compact digital camera than with earlier conventional analog film cameras. The minute imaging sensors of compact cameras need use of short focal lengths, and this in sequence gives these compact digital cameras an extraordinarily long depth of field when compared to other cameras. Thereby, with intent obtaining a shallow depth of field is more complicated.
| | How a digital camera worksWritten by Jakob Jelling
By Jakob Jelling http://www.snapjunky.comThe digital camera is not something of a magic box that came out of blue and made wonders! The digital camera is very much like conventional analog camera, but technology has been altered. It also contains most of associated components that conventional camera contains, like lens and a shutter for letting in light, however instead of reaching a photosensitive film, light is made to fall upon array of image sensors or photosensitive cells. Much of differences are like this, yet most of it still remains in oblivion for ordinary people. And it order that digital camera gets its true respect, it is necessary to explore these areas of truth and reveal them in light. Looking a bit more in details about working of fantastic device, digital camera. As a continuation of above lines, it can be further investigated that sensor array is basically a microchip about 10 mm across. Every image sensor is a charged-couple device (CCD) converting light into electric charges, and is essentially a silicon chip used to measure light. These charges are stored as analog data that are then converted to digital via a device called an analog to digital converter (ADC). Over chip are present a collection of very small light-sensitive diodes, named photosites, or pixels that convert light (or more scientifically, photons) into electrical charges called electrons. The pixels are very much light sensitive, therefore with brighter light striking them, produces greater build up of electrical charges. Each 1000 array receptor creates 1 pixel, and every pixel corresponds to some information stored. The light enters digital camera via lens, which is same mechanism as conventional analog camera. And this light hits CCD when photographer presses shutter button. The shutter opens and thereby illuminates every pixel, however with various intensities.
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