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Digital photography at its best
We have arrived at an era when digital media is more commonplace. It has become more cost effective, the results are pleasing, and the ease of sharing, viewing and archiving make it convenient for many users. History has shown that multimedia has gone through a continual evolution in regard to the use of formats and storage media. Many of us may confront issues regarding how we want to deal with photography. Should we consider the use of our own digital camera? The answer will depend on your views about how such a change would impact your life. Surely the consideration of owning a digital camera represents a collection of new challenges. This article will present an overview of some of the issues that are involved.
What is required?
The camera itself represents a substantial outlay of money, however it is not the only outlay that will be required. Fortunately, digital cameras are cost competitive with film cameras that may be used for most general purposes. The collection of features in a given camera will affect its price. A simple way of comparing digital cameras is by the number of Megapixels that show in an image frame. If you choose a one Megapixel camera, you will find that full-frame images will be slightly larger than the viewing area of a monitor screen that is set for a resolution (or screen area) of 800 X 600 pixels.
Another major determinant of adaptability is the zoom capability. The zoom range that is most significant to the user is the range of optical zoom. Digital zoom range is generally of less significance, as the user can deal with these settings while using an image modifying program after the image file is in the computer. Other features that may be of importance is whether you have viewing capability on the camera for seeing the image in a digital screen viewer before taking a picture as well as a digital screen that can show a selected image frame after the picture is taken. Provision for taking flash pictures may be an important consideration. Also, it is beneficial to have a display screen that shows how many pictures can be taken before the flash card is full.
Note that the flash card can be removed from the camera and replaced with a spare flash card, just as you would do with film cartridges. One difference is that the flash card is not light sensitive and its location in the camera is not in the light path that is used for taking pictures, so no precautions are needed before opening the slot where the flash card is installed. Closing the slot involves a mechanism that slides the card into position and makes contact to the pads. Opening the slot works in the opposite fashion and ejects the card just far enough that it can be grasped with fingers for removal.
You will find that savings will accrue when you dont have to pay for film or standard film photo processing.
Camera accessories that are often selected at the time of purchase can include things like a spare flash (memory) card, batteries, battery charger, carrying case, etc. Recognize that your total outlay will be dependent on whether a given accessory is included in the cameras price. A flash card has a thin substrate that contains a bunch of memory elements. It is slightly more than an inch on each side, and less than an eighth of an inch thick. It has a few plated copper pads on the substrate that provide connection points for applying power to it and for transferring signal data in and out of it. It is convenient to make these accessory selections at this time, as you are already at the location where they have the items and know which ones will fit your camera. However, accessories can be bought at any time from a reputable camera store.
You must consider the means for copying image frames from the flash card in the camera. If you copy these files to your own computer, there should be enough accessories and software bundled with the camera to provide for these needs.
The most common type of interfacing connection between camera and computer is a USB cable that mates with the camera at one end and with the computer at the other end. If your computer does not have a USB port available, perhaps the easiest way to add one or two of them is to use a USB card that gets installed in a PCI slot within your computer. This requires that your computer have and available PCI slot. If your operating system is Windows 98 or newer, chances are that Windows will see the new hardware and install the required driver for it when the computer boots after the USB card is installed.
The software for transferring image frames from the cameras flash card to your computer must be installed and the user must learn how to operate it.
There are so-called flash card readers which can be used to transfer data in or out of a flash card. The reader has the ability to accept dowloads from the flash card by removing it from a camera and placing it in the card reader. A reader will often serve as a writer if you have need for that, and a media device that can read from a flash card.
Another form of media used with some digital cameras is a floppy disk that inserts into the camera and is removed with images in JPG format. If this is the media used in a one Mpixel camera, you could get five shots on one disk, and may find that an indicator of how many remaining frames may be taken on a partially filled disk may not be important. This represents a very easy way to transfer image data to a computer.
Minimum system requirements for all new devices and software must be considered if everything is to work properly.
Other means of transferring image frames exist. To do so in conjunction with your computer, an external device can be purchased that will accept the flash card and will provide the ability to gather and retain the image files that can be copied to any available computer.
Another option is to take the flash card to a photo processor and have them provide the image files on a disk. Of course, this involves processing cost, but may not be as expensive as you expect.
Recent trends in battery selection for devices like digital cameras favor the NiMH, or Nickel-Metal Hydride type. They are more tolerant to many kinds discharge-recharge cycles, and will last for more recharge cycles than the Nickel-Cadmium types. They may give better service if a special charger is used with them. Some digital cameras use a custom battery and others use a few cells of standard size, like AA or AAA. Some users prefer to have two sets of them that are never mixed with members from the other set. One caution dont expect them to retain their charge as long as Alkaline or NiCad batteries. You may prefer that the batteries be of the standard AA or AAA configuration for a few reasons, one of which is that they are less expensive when buying as a spare or as a replacement than a custom battery. Also, you may be able to put in standard alkaline cells in an emergency.
Two forms of batery chargers are available, one for restoring charge when the batter(y) (ies) (is) (are) out of the camera, and one for replenishing charge when the batteries are in the camera, as the drain can be substantial when using the LCD viewer or when downloading pictures.
Taking pictures with a digital camera
Some differences in technique are required, as the digital image data is captured in a manner that is different from a film camera. Most digital cameras have a shutter that will make settings of focus and contrast when the shutter button is half-way down, and this process may add a delay to the time before the shutter operates.
When looking through a viewer, it is desirable to have a digital screen in the eyepiece viewer. One reason this is important is to ensure that certain types of scenes will retain the color elements correctly. A user should be aware that many digital cameras can do poorly with scenes such as sunrises if they point the camera at the foreground slightly below the horizon and in line with the sun before pressing the shutter. This may result in an image that shows none of the color or brightness of the sky. However, if you use the shutter button to pre-focus (and pre-contrast) on the sky, and hold the shutter button half-way down as your re-direct the camera toward the preferred framing direction, you will see if the colorful features in the sky will be retained in the picture. If you have a 2 Mpixel or 4 Mpixel camera, you dont need to point the camera in the preferred framing direction, as you can obtain a reasonably wide-angle result and unnecessary piture content can be removed later by cropping.
Generally speaking, a digital camera will use a shutter speed that is faster than a film camera, which relieves the user from having to steady the digital camera as much to avoid blurred pictures. The implications are that telephoto work can be done with a digital camera without a tripod if the user is steady, the camera has considerable zoom capability, and the scene is well lit. This is an interesting result that can be obtained without an expensive and heavy detachable lens, which would be required on a film camera. Also, many digital cameras have an autoexposure feature that tends to make a setting of fast shutter and fast f-stop. Thus, an amateur photographer can do a respectable job with telephoto photography, where the narrow-angle view may be the only manual adjustment needed for point-and-shoot pictures. Because the fast shutter speed makes the camera more tolerant of slight motion while taking a picture, some have come to regard this effect as a virtual stabilizer. In more expensive cameras, many will have a feature called image blur reduction. This is especially useful when taking telephoto pictures. Read the instruction manual for the camera to set up this feature. It may require that you press the shutter button halfway and hold it for a second or longer for this feature to become operational prior to operating the shutter.
Some of the better digital cameras do can an excellent job of taking close-ups, as their focus range may include four inches to infinity.
With the digital viewer on the back of the camera, you can have some assurance that a satisfactory photo has been obtained. However, it has limited resolution and limited ability to show a good display in sunlight. You can delete images from the flash card that you dont want and free up memory for additional frames to be shot on the same flash card.
For most purposes, a user will be satisfied with images in the JPG format. With a 2 Mpixel camera, each frame will require about 0.5 MB of file space. Thus a 32 MB flash card will serve to retain up to 64 image frames.
telephoto photography
Tags: Canon, DSLR, Nikon
