
Light metering modes
Light metering - it is illumination or sunniness measuring of the object, which we want to make picture of. Exposure and quality of the future image highly depends on correct measurement of the light metering and you have to be very careful and treat this matter with great responsibility. If camera, you have, defines measurement type itself by default, probably it's not very expensive model, which will not allow you shoot excellent pictures in difficult light conditions.
What types of light measurement do we have?
Usually, there are three types of measurements.
For example, in common conditions, if all object is highlighted evenly, and there are no separate bright or dark areas, we use Evaluative Light Metering mode. In this mode the camera divides image into several zones for light metering. After that camera evaluates the complex lightning conditions, such as the position of the object, the brightness, the direct light, the background, and the backlighting, and adjusts the settings to the correct exposure for the main object. This mode is particularly well-suited for backlight conditions and general photography.
If you make portrait, you need to use Center – Weighted Averaging mode, when camera averages the exposure from the entire image, but places more weight on the subject at the center.
When you are shooting pictures at the theatre or ballet, for instance, when lights are down, and actor is lighted up, most useful in this case will be Spot AE Point mode. If you measure light through all of the area of the frame – you certainly will make it overexposed. When you work in difficult light conditions – you can't go without Spot AE Point mode.
Camera's auto modes
In many(if not all!) modern cameras provided auto modes, where pair of values – shutter speed & aperture set by the camera by default. When you change one value, another changes automatically, preserving correct exposure.
1. Av mode – Aperture priority
In this mode photographer specifies aperture and shutter speed changes automatically, according to the light conditions.
Advice
When doing portraits, you need to open aperture to values 2,8 or 4,0. When you are shooting
landscapes or interior – you need to close aperture to values 8 or 11, to get the best image sharpness.
2. Tv mode – Shutter Speed priority
Working with this mode, photographer sets the shutter speed, and aperture value changes automatically. Use this mode, while shooting images at the sport events. This mode also handy when you work with flash.
3. P – Program AE
Camera sets itself shutter speed & aperture. In some cameras photographer may change these pairs, controlling these changes in viewfinder.
4. M – Manual mode
In this mode everything depends on the photographer – you may set any values aperture – shutter speed and camera will advise you about correct light metering and what is the difference between necessary exposure and that, you have chosen.
Depth of field
With precise focusing on certain object there is always will be sharp not only that object in the image, but its surroundings. All other space can be blurry. And how much that surroundings will be blurry depends on Depth of field.
For example, if lens is focused on object, distant for 4 meters, and all other objects, located in front of that object and behind from 3 meters to 6 meters will be quite sharp – this area is depth of field.
Depth of field depends on chosen aperture. The more aperture is opened (values 2,8; 4), the smaller depth of field sharply pictured area. The more aperture is closed (values 5,6; 8; 11; 16), the more chances you have to get area with the same sharpness in front and behind the object.
Depth of field also depends on focal length. The more focal length has camera's lens, the longer lens, the smaller seeming depth of field.
For example, wide-angle lenses have practically sharp all image area, if you set aperture for values of 8 or 11 and focused lens for infinity. It is possible to focus lens on some hyperfocal point somewhere in the middle, and as a result – foreground and background will be sharp as well.
Advice
If you make photos at zoo through the cage, take long-focal lens, open aperture at maximum and come as close to the cage as possible. Focus your camera on the animal and cage will be gone to the blurred, almost invisible area.
With this article of Day 3 we finished our discussion about main conceptions in photography. After this, armed with the basic knowledge about cameras, we may continue our journey, and later we will talk about:
Right selection of the camera
Fundamentals of the composition in photography
Light and Colour in photography
How to use Flash in photography
How to shoot portraits
How to shoot landscapes and animate nature
How to do picture story
How to shoot images at night
How to make pictures of the sporting events
How to make photos at the theatre
How to store and organize your photo-archive
How to sell your photos online and earn pretty good revenue
and much more...
If you would like to learn more about photography from the top experts and sharpen your skills and become the master of photography, you will find all necessary information here http://www.cbmall.com/to/photowizard

