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Digital Camera Features
What Are All of Those Digital Camera Features?
Digital cameras offer casual users a lot of automated functions to assure they get good results. Of course many of these digital camera features can also be controlled manually if you understand how they work and when they should be applied.
To help the novices out there, I put together this page to explain some of the more common features and functions you'll find on today's digital camera.
Photo by: Vibrant Spirit. No derivative work allowed.
Pixels and Resolution
Digital images are composed of tiny units called pixels. Each pixel is distinct with it's own color and intensity. When resolution is discussed it refers to the number of pixels, or units of information, that make up the image. More pixels mean higher resolution. The larger the image, the more pixels are needed to give the image the clarity desired. Thus a 4x6 image requires fewer pixels for high quality than a 9x10 image. This is why a 3 megapixel camera may produce nice 4x 6 images but a camera with a 5 or 6 megapixel sensor may be need to produce a 9x10 image with similar quality.
For casual users, cameras that offer a 10, 12, or higher pixel sensor are often not necessary. The additional pixels are useful primarily if you will be producing very large prints or perhaps when zooming or cropping photos a great deal as the additional pixels can help prevent excessive loss of quality due to these processes.
In some instances, cameras that offer 12, 14, or more megapixels can be a problem. The average point and shoot digital camera has a small sensor. Say 1/2.5" or so. This doesn't generally change as they add in more pixels. Those pixels then get smaller as more are crammed onto the sensor. Smaller pixels gather less light. Therefore, these cameras can take poor quality low light and action shots. If you buy a camera with a high megapixel count, then the sensor will need to be larger to accommodate those pixels and create high quality images in these situations.
One of the most common problems casual photographers have is blurry, indistinct, or poorly focused pictures. This is often a result of unintended hand movement or shaking. The camera movement is especially evident when zooming in on something, when taking up close shots, or low light shots when the camera uses a slower shutter speed. Of course, using a tripod can eliminate this, but many of our shots are handheld. To offer at least a partial solution, digital camera features now often include some type of image stabilization.
Some digital cameras offer optical image stabilization which is a mechanical process that helps to counteract this inadvertent camera movement to provide a clearer, more focused image. Other cameras offer digital or electronic image stabilization which is an electronic process. Some manufacturers call this anti-shake technology as well. Unfortunately the use of digital image stabilization can increase the "noise" in the resulting photograph. This noise makes the image look grainy. For this reason, true OIS is superior to digital IS.
Image stabilization will not compensate for blurriness caused by the movement of your subject. If you want to capture a subject in movement without blurring, you would need a faster shutter speed. If your camera doesn't allow you to manually adjust the shutter speed you can often choose the action or sports shooting mode for better results.
Zoom is one of the digital camera features that even most ultra compact cameras offer. Zoom allows the user to get a closer shot of subjects even when they can't physically get closer. Just as with image stabilization, digital cameras may offer either optical or digital zoom. In fact, many cameras will offer both. In such instances, your digital camera will generally use optical zoom to it's fullest range and then, if you continue to zoom, begin to utilize the digital process to produce an even greater zooming effect.
Optical zoom will utilize the lens to magnify the image to bring you closer. The quality of the image that the camera produces will not deteriorate using optical zoom. On the other hand, digital zoom is an electronic process which crops the image and then enlarges the remaining portion to make it look as if you have zoomed in closer. Because the number of pixels in this portion of the image is not increased, the resulting image has lower resolution. For this reason, optical zoom is preferred as it doesn't erode image quality. The negative effect of digital zoom however, is generally noticeable only in larger prints or if you will be further cropping the image when you edit your pictures.
Autofocus is another extremely useful digital camera feature that allows even beginners to produce great images. Autofocus simply means that the camera will identify your subject and make adjustments to get the best focus. Typically, the camera will identify your subject as the item or person in the center of your shot. This focusing is the primary reason that many digital cameras have a delay between pressing the button and taking the photo. In most instances, it's appropriate to press the shutter button down halfway to engage the autofocus, and then once this is done, to fully depress the button to capture the shot. In most instances, you can see what it has identified as the subject or point of focus, by a box that appears on the LCD screen as you first begin to press the shutter button.
Some cameras also have what is called multi-point autofocus.These cameras will identify multiple points upon which to focus. The user can have the camera select the one it wants, or choose the one they wish for it to focus upon. This allows you to set focus on a subject that is not in the center of the shot.
Red Eye Correction or Red Eye Reduction
If you've viewed informal photographs of people, or pets, then you've probably seen the red-eye effect. Red-eye is the result of the flash reflecting off of a person, or pet's eye. Getting your subjects to avoid looking directly into the camera can help to eliminate this problem. However, getting small children and pets to avert their eyes isn't always possible.
Luckily many digital cameras now offer red eye reduction. This is an automatic feature that allows the camera to make adjustments to prevent red eye effect in your photos. Some cameras provide red eye correction or removal in the editing phase as well. Even if your camera doesn't have this feature, many editing programs allow you to perform this function as well.
Shooting and Scene Modes
Getting the right focus and exposure on a given shot may require some adjustments based on the situation. For instance, the shutter speed for a night shot may need to be slower than for a shot taken during the day time in order to get enough light. In addition, the lens aperture (opening) may need to be wider for the same reason. White balance, sensitivity and so forth may also need adjustment to get the kind of image you want. Luckily for casual users, the average digital camera features include a variety of shooting and scene modes to make this easy. Users who want more control in creating their photographs can use the manual mode or perhaps an aperture priority or shutter priority mode when desired.
For the rest of us, scene modes and shooting modes allow us to make the necessary adjustments with the press of a single button. Beach, snow, night, night portrait, portrait, landscape, action/ sports, pets, and so forth are common modes you'll find on a camera. Video mode is a newer option but obviously it allows users to capture movies. Most of these modes are fairly self-explanatory but a few may need further description.
Macro mode is useful when focusing on subjects up close. All cameras have a range at which they can focus. Typically 3 feet is about as close as you can get without things getting out of focus. Using macro mode however, you can often get within a few inches and still get a quality image. Burst mode gives users the ability to take several shots in rapid sequence without having to press the shutter button each time or waiting for the camera to store each image. This mode is perfect when trying to take pictures of movement. Burst mode is also called Continuous Shooting Mode.
If you know the types of shots you'll be taking, then you can check to be sure the camera you're considering has just such a mode to give you the best results.
In digital photography ISO relates to the sensitivity of the image sensor to light. Generally speaking a lower ISO setting results in very little "noise" in your photograph. Lower settings are fine when there is good lighting. However, when there is less lighting, a higher ISO setting is needed; as well as a slower shutter speed and wider aperture potentially. Most compact digital cameras can make these adjustments automatically or manually.
If you will be taking low light or night shots, it can be important to select a camera that has a high ISO setting available; ISO 3200 or better. To learn more about ISO settings and noise, you can review this article.
A function on your digital camera that most casual photographers will leave set on automatic is the metering mode. Metering mode basically determines how your camera will expose a picture. Within a scene there may be a range of lighting. For instance, you may be standing in a room with low lighting and shooting toward an area of the room with a lamp or a window nearby that has greater lighting. The camera has to decide which area of the shot to expose correctly. It often takes an average of the areas. This is known as zone or multi-segment metering.
Many cameras however can also use spot metering where the camera is told to choose it's exposure based on a particular spot within the scene; this may be in the center of the scene or it may be off-center. This can be a fairly precise method of determining exposure and can give great results when there are dramatic differences in the lighting within a scene. Center-weighted metering, as the name would imply, determines the exposure based on the lighting present in the center of the shot.
If you want to learn more about specific metering modes, you can review this Wikipedia article.
Different sources of light have different color characteristics. Some lights, like incandescent, have a red cast, often giving photos a more yellowish appearance. Fluorescent light on the other hand has more blue cast. Luckily your digital camera features include White Balance which is how your camera attempts to eliminate any unnatural cast from the various light sources.
Auto white balance will make all of the decisions for you, and in many shooting situations it can do a good job. However, many point and shoot cameras also offer white balance presets, that allow you to make adjustments with the press of a button. Tungsten, sunny, cloudy, fluorescent and others are among the selections.
Of course, for those who are more skilled, many digital cameras also allow you to manually adjust the white balance. You can find some help in doing this by reviewing this article. In some instances, rather than achieving the perfect white balance a user may want a particular color cast to their photograph for creative purposes. Adjusting the white balance can allow this as well. Of course, many image editing programs also allow you to adjust white balance or add filters to achieve similar results.
Face detection or face recognition has become one of the more popular digital camera features in recent years. It allows the camera to identify faces in a shot and to automatically adjust the focus, flash, and exposure to get the best shot of your subjects.
If your camera has a tracking function then it will be able to place priority on a particular face within a group or crowd.
Smile and Blink Detection
Smile and blink detection can help casual photographers be sure the human subjects they photograph are captured while looking their best. The camera is able to detect when a smile occurs, focus, and take the picture at just the right moment. If a camera has this feature, you can turn it off if you don't choose to use it.
Generally, blink detection is a feature that simply allows your camera to detect when a subject has blinked as the photograph was being taken. It alerts the photographer of this on the LCD screen so that they know to re-shoot the photograph to get the results they want. Some cameras handle this differently, for instance they may also automatically shoot the second picture when a blink occurs rather than just alerting you to the situation. Users would need to review their user's manual to know exactly how this feature functions on their particular camera.
As we described above, noise can erode the quality of a photograph by introducing artifacts or a graininess to images. Noise can come from the internal electronic components of the camera or high light sensitivity among other things. Many image editing programs allow you to reduce this noise to improve image quality. Among common digital camera features however is a noise reduction function too. It can be useful, especially in low light shots when higher ISO settings (sensitivity) are needed. However, if you are shooting in normal lighting or up close, it can decrease the clarity and detail of the photograph. Some cameras have this as an automatic function but some offer it as a user controlled feature.
Some digital cameras now offer a "Sweep Panorama" mode. This feature is designed to make capturing true panoramic images much easier. With this mode the camera will capture images continuously as you sweep a scene and will automatically "stitch" those images together to create a panoramic image.
Back Illuminated Sensors
This isn't a feature as much as it is a part of some digital cameras. A backlit or back illuminated sensor will provide much greater light sensitivity without increasing noise or artifacts in the resulting images. This means that when you are shooting in low light particularly, your images will have better clarity and more brightness. Many high ISO settings help a digital camera pick up light in these situations but because of excessive noise, the images are still poor, these back illuminated sensors help remedy this problem.
A backlit sensor isn't the only characteristic to consider if you want good low light performance or fast action shooting but it's one part of the equation.