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White Balance is an automatic or manual control that adjusts the brightest part of the scene so that it appears white. Every time a digital camera takes a picture it needs to establish a 'white point.' Many digital cameras offer an auto white balance setting as well as preset white balance settings and manual white balance settings. When the camera is set to auto white balance mode, the camera decides where the white point is in the photograph. The preset modes (i.e. sunny, cloudy, fluorescent, tungsten/incandescent) are to be set each time you move to a different lighting situation. For example, one would not want to use sunny white balance mode when under tube lighting - you would want to use fluorescent white balance mode for this situation. The manual white balance mode allows you to pick a specific color temperature.
*The diagram above are approximate temperatures that will correspond to each type of light. These temperatures will vary depending on the condition. If it is a mostly sunny day with some clouds the temperature will vary slightly.
*Information from Judith Pisconeri and Light and Lens. www.pisconeri.com
Aperture: is the lens opening and controls how much light is passed through the lens.
F.Stop: are the numerical measurements of the Aperture.
As you can see in the diagram above the lower the number (i.e. F2) the larger the opening of the lens which allows MORE light in. On the flip side, the higher the number (i.e. F22) the smaller the opening which allows LESS light in.
So what's the big deal? Why is Aperture/F.stop important?
One of the important things the f.stop/aperture affects is the depth-of-field. The f.stop/aperture on the lens controls how much of the image is in focus in addition to the point you specifically focused on. For example, a lower (wide-open) aperture (i.e. F 2.8/F4) will produce an image where only the subject focused on is sharp, and the items in front of and behind the focus point are out of focus in varying degrees. A higher aperture (less opening in the lens - i.e. F11/F16 +) will produce images with more or all of the subject and surroundings in focus.
*Information from Judith Pisconeri and Light and Lens. www.pisconeri.com
Here is a crude diagram I quickly put together so that we can have a discussion on 'in-camera' light meters. (Depending on the model of your camera- the plus and minus side may or may not be on the same side as this diagram.)You will notice in the diagram that there are two bolder/bigger lines to the minus side and plus side of this diagram. These are STOPS. If your meter reads to the first bold line on the minus side it means that you are 1 stop underexposed. If you are at the second bold line on the plus side it means that you are 2 stops overexposed.
So, how does a light meter work? The camera's light meter reads the light reflecting back from the 'scene' you have selected in the viewfinder. The meter then determines the average exposure within the scene.
Change the MODE of your camera to MANUAL. You will then need to change your shutter speed and f.stop to make the meter read 0. Helpful Hint: Go outside during daylight hours. Set your ISO to 400. Set your shutter speed to 60. Then, all you need to do is change your f.stop until you reach 0. Once you have taken a few different photographs using this method, try setting your f.stop to 5.6. Then change your shutter speed until you get to 0. Repeat these a few times in different locations. (Remember that you should not go under a shutter speed of 60.)
Once you have familiarized yourself with your meter and using your shutter speeds and f.stops to get to 0 you might want to try bracketing.
Exposure Bracketing begins by making a 'correct exposure.' Then you make a picture one stop below the 'correct exposure' and finish by making another picture one stop above the 'correct exposure.'
Example: Original or 'correct exposure' Shutter Speed: 125 F.Stop: 8
Under: Shutter Speed: 125 F.Stop: 11
Over: Shutter Speed: 125 F.Stop: 5.6
*Information from Judith Pisconeri and Light and Lens. www.pisconeri.com
There are many 'terms' in photography and it is important to familiarize yourself with them. Below are a few important terms. I will go over them in more detail as time progresses.
Shutter: timed operation on a camera.
Focus: there are two ways to focus a camera. Auto focus - the camera will focus for you. Manual focus - you have to focus the camera/lens.
Aperture: the opening in the lens
F-stop: The measurement of the opening of the lens associated with a numerical number. (i.e. the opening of the lens at an f-stop of 2.8 is much larger than the opening of a lens at an f-stop of 22).
Shutter Speed: How long the shutter is open. On manual mode-it is important to begin shooting no lower than 60. This is 1/60 of a second. If you go lower than this number - your image may be blurry due to camera shake.
ISO/ASA: This is essentially the same as film speed. The higher the ISO, the less light you will need. (i.e. outside on a bright sunny day you can shoot at ISO 100. Inside with normal house lights you would shoot at an ISO of 400). *A good rule of thumb for what ISO to shoot at: somewhere between 100-400.
