The time has come. You are in charge of your 25th high school reunion, so it is up to you to collect everyone’s senior pictures and “Most Likely To…” photos from your yearbook. You need to invest in a scanner. But where do you begin? What should you look for in a scanner?
First of all, it is important to know what a scanner is and does. A scanner is a device that converts printed material into digital information that your computer can use. Using a small electronic component, it records how much light is reflected off the material being scanned, and reports that information to the computer. In order to see the entire image, it is broken into cells, called pixels.
Next, consider what kind of scanner you need. Currently, there are four primary types of scanners available from which you can choose, including:
1. Flatbed – This is the most common type of desktop scanner. The flatbed looks a bit like a small photocopier, and the item being scanned rests on a glass plate while the scanning head moves underneath it. (For the project of scanning old yearbook photos, this scanner should be ideal!)
2. Sheet fed – These are similar to fax machines, in that they move the page being scanned past the scanning head. While a sheet fed scanner may be a good choice if you need to scan in volume, it is not ideal for precision-quality output, since it is difficult to scan a moving sheet of paper without some distortion of the scanned image.
3. Slide – The slide requires the scanner to pass light through the image, rather than reflecting light off of it. Also, because of their small size, slides must be scanned on a unit with very high resolution.
4. Drum – Drum scanners are the most effective and versatile of all scanners, but they are more expensive and slightly more difficult to operate. Because drum scanners typically use high-quality photo-multiplier tubes and the material being scanned is rotated past the scanner heads numerous times, the resulting scans are much more accurate.
Now you have an idea of what kind of scanner is best suited to your needs, but there are a few other considerations before you actually make your purchase, including resolution, bit depth, scan area requirements, scan head options, and scanner ports.
Resolution – Having determined which scanner you need, it is important to check the scanner resolution (the amount of pixels a scanner can see, usually give in dots per inch (dpi), because it determines how detailed the scanned digital image will be. A good rule of thumb is: the higher the scanner’s resolution, the better the scanned image. If your scanning needs are in large, detailed format, a high resolution scanner is critical. Scanner resolutions range from 600 by 1200 dpi (low end) to 2400 by 4800 dpi (high end.) For general home use, like scanning high school pictures, 300 or 600 dpi is really all that is required. Any more than this requires lots of disk space, and the detail achieved is virtually undetectable to the naked eye.
Bit Depth – Scanners with higher bit depths tend to produce better color images. A scanner “looks” at the image, pixel by pixel, and records what it “sees”. However, different scanners record more information about each pixel, and this is known as its bit depth. Most color scanners available on the market today are a minimum of 24-bit, which means they collect eight bits of information about each color (red, blue, green, etc.) A 24-bit unit can actually capture more than 16 million different colors! (This near-photographic quality is also called “true color” scanning.) While there are some 30 and 36-bit scanners available in the marketplace, there are few compatible software packages; they simply cannot handle so much detail.
Scan Area – Another important consideration when choosing a home scanner is the scan area you will need. If you are planning to scan large documents (i.e. maps, newspapers, posters, etc.) A large scan area is important. Generally, low-end scanners have scan areas of 8.5 x 11.7 inches; high-end scanners typically go up to 8.5 x 14 inches.
Scan Head Technology – For the average household scanning needs (like scanning yearbook pictures) scan head technology is not a critical feature, but it is good to know what is available. Currently, there are two kinds of scan head technology: CCD (charge-coupled device) and CIS (contact image sensor). Typically, CIS-based scanners are smaller than CCD scanners, and usually do not require a separate power cord.
Scanner Ports – Most scanners sold today come with a USB 1.1 port, while some newer models have USB 2.0 ports. The computer you will be plugging your scanner into must have a port compatible with the scanner or it will not work, so double check your home computer port and note what it is before making your scanner purchase.
Author:-YUNG TRANG
First of all, it is important to know what a scanner is and does. A scanner is a device that converts printed material into digital information that your computer can use. Using a small electronic component, it records how much light is reflected off the material being scanned, and reports that information to the computer. In order to see the entire image, it is broken into cells, called pixels.
Next, consider what kind of scanner you need. Currently, there are four primary types of scanners available from which you can choose, including:
1. Flatbed – This is the most common type of desktop scanner. The flatbed looks a bit like a small photocopier, and the item being scanned rests on a glass plate while the scanning head moves underneath it. (For the project of scanning old yearbook photos, this scanner should be ideal!)
2. Sheet fed – These are similar to fax machines, in that they move the page being scanned past the scanning head. While a sheet fed scanner may be a good choice if you need to scan in volume, it is not ideal for precision-quality output, since it is difficult to scan a moving sheet of paper without some distortion of the scanned image.
3. Slide – The slide requires the scanner to pass light through the image, rather than reflecting light off of it. Also, because of their small size, slides must be scanned on a unit with very high resolution.
4. Drum – Drum scanners are the most effective and versatile of all scanners, but they are more expensive and slightly more difficult to operate. Because drum scanners typically use high-quality photo-multiplier tubes and the material being scanned is rotated past the scanner heads numerous times, the resulting scans are much more accurate.
Now you have an idea of what kind of scanner is best suited to your needs, but there are a few other considerations before you actually make your purchase, including resolution, bit depth, scan area requirements, scan head options, and scanner ports.
Resolution – Having determined which scanner you need, it is important to check the scanner resolution (the amount of pixels a scanner can see, usually give in dots per inch (dpi), because it determines how detailed the scanned digital image will be. A good rule of thumb is: the higher the scanner’s resolution, the better the scanned image. If your scanning needs are in large, detailed format, a high resolution scanner is critical. Scanner resolutions range from 600 by 1200 dpi (low end) to 2400 by 4800 dpi (high end.) For general home use, like scanning high school pictures, 300 or 600 dpi is really all that is required. Any more than this requires lots of disk space, and the detail achieved is virtually undetectable to the naked eye.
Bit Depth – Scanners with higher bit depths tend to produce better color images. A scanner “looks” at the image, pixel by pixel, and records what it “sees”. However, different scanners record more information about each pixel, and this is known as its bit depth. Most color scanners available on the market today are a minimum of 24-bit, which means they collect eight bits of information about each color (red, blue, green, etc.) A 24-bit unit can actually capture more than 16 million different colors! (This near-photographic quality is also called “true color” scanning.) While there are some 30 and 36-bit scanners available in the marketplace, there are few compatible software packages; they simply cannot handle so much detail.
Scan Area – Another important consideration when choosing a home scanner is the scan area you will need. If you are planning to scan large documents (i.e. maps, newspapers, posters, etc.) A large scan area is important. Generally, low-end scanners have scan areas of 8.5 x 11.7 inches; high-end scanners typically go up to 8.5 x 14 inches.
Scan Head Technology – For the average household scanning needs (like scanning yearbook pictures) scan head technology is not a critical feature, but it is good to know what is available. Currently, there are two kinds of scan head technology: CCD (charge-coupled device) and CIS (contact image sensor). Typically, CIS-based scanners are smaller than CCD scanners, and usually do not require a separate power cord.
Scanner Ports – Most scanners sold today come with a USB 1.1 port, while some newer models have USB 2.0 ports. The computer you will be plugging your scanner into must have a port compatible with the scanner or it will not work, so double check your home computer port and note what it is before making your scanner purchase.
Author:-YUNG TRANG
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