Basic terms you must know- in easy to understand words
What is a camera? How does it function. Lets try to understand it in a simple manner. Camera is a light tight container and does not allow any light to enter till we want it to. The process of allowing the light to enter the camera for a certain time duration, through an openning is what is called "taking a picture" in simple words. this opening in the lens is called "aperture" and the duration for which the film is being exposed is called "shutter speed". To take a picture you need to release the shutter, i.e uncover the film/sensor. At this point of time the aperture opens to the size that is set on the camera and allows the light to enter through the set size. The momment the film gets the light for the set time frame the shutter covers the sensor/film again and is back in position, ready to take another picture. This combination of shutter speed and aperture (at a given ISO) is called exposure. We may have various combinations depending on the desired effect in the photograph.
The diameter of the lens diaphragm can be changed by turning the aperture ring. This dictates the brightness of the image reaching the film. Moving to the next f-number either halves or doubles aperture size. Aperture size also effects depth of field.
The shutter speed is the duration for which the aperture remains open and hence the film gets exposed. Do not confuse yourself with the word "speed". It is not the speed with which the shutter moves.The shutter can be set at different speeds, which determine the length of time the film is exposed Moving the shutter speed dial to the next stop either doubles or halves exposure time.
This is the plane where the film/sensor is positioned inside the camera body. This is where the image is formed when the lens is focused on the subject.
FOCAL LENGTH-
There is a setting on the lens which lets you see more or less through the viewfinder.If you move this dial in aprticular direction, then you see less area but you see more far off area. This changes the angle of view. Decides how much is to be included. For example, if you are shooting a group of 5 people, from the same distance with a wide angle/short focal length you may be able to include all and with a telephoto or long focal length you may be able to get only one person in the frame. framing and focusing are two different things. Framing is concerned with how the photograph is composed and focusing is concerned with how sharp the subject is. More about focal length.
This is the dial on the lens which lets you focus / keep a subject at a specific distance at sharp focus. This decides the sharpness or blurness in the photograph
AUTOFOCUS-
The camera focuses itself at the selected focusing point. Cameras have a number of points vissible in the viewfinder which may be chosen as per the position of the subject in the frame. Some people feel that they should focus manually as a learner. In fact autofocus saves a lot of precious momments which may rather be used for decisions reagarding the composition and aesthetics rather than rotating and strugling with the focusing dial of the lens. However, there may be certain situations when autofocus may get fooled and not work very well. this is when the human intelligence may be utilised by focusing manualy. Also, manual focusing may be preffred by many photographers for macro photography.
BLUR- when the image is not sharp. Can be either due to wrong focusing r due to the camera shake. If the focus is at a point closer or away from the subject distance and there is not enough depth of field, the subject will be blured
If the camera is hand held and the shutter speed is lower than 1/60th sec the camrea movement will get registered in the photograph. Ways of reducing the Blur.
Besides the focusing point (which you may have achieved with the focusing dial) you may still keep the element at other distances in focus or out of focus. If everything or most of the things in the picture appear to be very sharp, it means there is great depth of field. If only the main subject is the focus and the rest of the elements in the photographs are blurred, the depth of field is shallow.
Exposure is the combination of aperture and shutter speed at a given ISO (sensitivity of the film/sensor)
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Metering is the way the camera interprets the existing light and suggests a suitable exposure.The metering modes or the exposure decides if the image is brighter, darker or the same as it exists in reality. generally there are three metering modes- multi pattern, center weighted and spot.
How the subject has been framed or positioned in relation to other elements in the photograph.
This dictates the sensitivity of the film or the sensor. More is the number relatively less is the light required to expose the shot. If the iso is more you may either be able to close down the aperture more or you may be able to set a faster shutter speed.
This is the sensor fixed at the focal plane where the image is formed when a photograph is taken. In other words, when exposed to light it reacts electroniically to form an image. (On a film, this is a chemical reaction) This is actually digital information which is further transfered to the memory card. Generally people consider the number of pixels on this sensor but the size of the sensor is also important. A 6 megapixel camera would have 6,000,000 pixels with 3 accross the length and 2 accross the width of the sensor. Full frame sensors are the ones which are of the same size as 35mm film. simmilarly ful frame sensors of medium format digital are equivalent of the size of a 120mm film (6x4.5cm)
More the number of megapixels- beter is the picture quality. Also bigger is the sensor size - beter is the picture quality. making large sensors is more difficult and expensive, which is why companies market their cameras around the numbers. Having more number of pixels on a smaller sensor does not lead to improvement in quality.
File formats-
RAW- as the name sugests, this is how the image is shot and stored when photographed. This is the unprocessed form of information and any alteration on this with the software is almost as good as changes made during the original exposure. If your exposure was not corect while taking the picture you can still corect it but dont get into the habit of shooting wrong. Ideally, one should always shoot in RAW. Even if you need to use jpeg images, it is still beter to convert it using the software than the camera. The camera always shoots in RAW and internaly converts and stores in jpeg on the memory card.
If you are unsure of your skills it rather safer to shoot in RAW, than to shoot in JPEG. Also, on the colour calibrated computer monitors, one has a beter control to fine tune the exposure, white balance, saturation, contrast etc. Once again, this does not mean that you shoot wrong. There is nothing to beat-shooting right to begin with.
This is a reusable recording media used in the camera to write the image as it is recorded on the sensor. Compact flash (CF) and Secure digital (SD) are the most common ones. Like a hard disk, these are also vulnerable to physical shock. Never drop them. Keep the contacts clean and insert them in the camera or the card reader very carefully so as not to bend the delicate pins in side the card slot of the camera.