Before I get into a discussion about how the light meter works, think about the last time … Your camera’s light meter is like measuring the temperature using a meat … or ISO would make the triangle move up or down the line accordingly and result … You will often see wedding photographers using a light meter such as this in …

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Shutter speed
shutter speed also known as “exposure time” stands for the length of time a camera shutters open to expose light into the camera sensor .If the shutter speed is fast ,it can help to freeze action completely .If the shutter speed is slow it can create an effect called "motion blur"where moving objects appear blurred along the direction of the motion.This effect is used quite in advertisements of cars and motorbikes.
• Aperture

Medium
Medium of light is also very important in photography.photographer has to check which medium is being used in the photography either its sunlight, bulb light or any other indoor light .Techniques of the photography vary according to the medium of photography.

Light To make a picture you require light ,that light may be natural or artificial such a as a light bulb or flash .Light that our own eyes are sensitive to 9 is called a visible light .But other creatures and material are sensitive to non visible forms of light such as Ultraviolet light ,infrared or x-rays.

Composition
Main factor of composition is rule of third Rule of third can be done manually by cropping too.

Optics
Optics or lense are very important in photography .There are different kinds of lenses used in photography like standard lense ,wide angle lense, Telephoto lense, Zoom lense, Fish eye lese, Macro lense, Tilt shift lense and image stabilization lesne.The choice of the length depends on your type of photography.If you want to shoot outdoor you will need wide angle lense but in indoor photography vivid range of lenses are use to cater different types of photography.

Solution:
Dust is everywhere and everywhere is dust. It will get on and inside your lens. Lenses are manufactured in extremely clean factories, where manufacturers go to great lengths to try to eliminate dust from the environment. Even then, brand-new lenses may have dust between the lens elements.
Dust, however, is not the main enemy. A lens that sits on a shelf in your home for years and collects a thick layer of dust will, obviously, produce image-quality issues. But, a few specs of dust here and there on or inside the lens will have no effect on image quality. A few specs of dust on or inside the lens will have no effect on image quality. That statement was intentionally repeated.
Trying to keep your lenses dust free through continual cleaning may serve to shorten the life of your lens, as you run the risk of scratching the lens surfaces every time you clean the glass.
Remove as much dust and dirt as possible from the lens with a blower or soft bristled brush.
Apply a few drops of lens cleaning solution to a lens tissue or cleaning cloth.
Using a circular motion, gently remove oil, fingerprints, and grime from the lens surface, working from the center outward.
Note:
This is only solution making ides, not a complete solution.