Scanners
A scanner is a quick, easy and high-quality way to get words and pictures into your computer.
From digitising old photos to carrying out a range of vital office functions, you’re never stuck when you have a scanner. They come in two main types: flatbed and film. A flatbed scanner offers more options and uses whereas a film scanner is great for detail. Also, many modern models now include a whole raft of extra features to keep you busy such as image-editing software and optical recognition.
Which type?
Flatbed
Choose a more versatile flatbed model and you will be able to scan in both photos and documents. However, quality could be an issue here as the resolution on these models differs greatly. Flatbeds use a CFC (Cold Cathode Fluorescent) lamp to scan, which are known to produce relatively stable colour accuracy. LED light sources are also being used in some of the latest scanners – these are quicker to heat up than CFC but achieve the same quality.
Film:
With a film scanner you will be able to scan in negatives, slides and camera film. But if you want to scan APS film you may need to buy a separate adaptor. Film scanners can offer excellent resolution and quality depending on how much you are willing to spend. But remember – they can only scan negatives.
The best of both worlds: Some flatbed scanners come with accessories that allow you to turn them into a film scanner. This is done by fitting a photo lid to the top of the scanner. Although these will scan film and negatives, the results will only be as good as with the flatbed.
Things to look out for
Resolution
Resolution is measured in dots-per-inch (dpi) which indicates how detailed a reproduction of the original document a scanner can make. As with printers, the higher the dpi, the better quality the scanned image will be. Generally speaking, 1,200 dpi is fine for everyday tasks. But if you’re scanning film then 2,400 dpi will be more like what you’re looking for.
Optical Character Recognition (OCR)
This software allows a scanner to ’read’ text and turn it into an editable word-processing document without losing the formatting of the original. If you have a stack of old letters or documents that you want to convert into digital files, this is the way to do it.
Image-editing software: The image-editing software provided with many scanners is often based on expensive, established programs which have long been used across the design industry. You will be able to use the software to carry out editing tasks such as altering the colour of a poster or carrying out basic restoration on an old photo.
Bit-depth
Bit-depth is a good indicator of how detailed and colourful your scans will be. For instance, a scanner with a high bit-depth will be capable of picking up more colours and detail than one with a low depth. Each pixel needs 24-bit to create true colour. Most scanners are now 48-bit which is easily good enough to meet most people’s needs. Bit is short for binary digit. It has a single binary value of 0 or 1.
Interface me
Before buying your scanner, ensure you know what interface system it operates for plugging other devices in. So, if your computer has a USB port, it’s no good buying a scanner with a Small Computer System Interface (SCSI) and so on. The SCSI connects your computer to other devices and is factory fitted with most PCs.
Awaken the senses
Scanners use three types of sensors: Contact Image Sensor (CIS); Complementary Metal-Oxide Semiconductor (CMOS) or Charged Coupling Device (CCD). A popular choice for flatbed scanners is CCD, which is similar to the sensor used in digital cameras. Scanners using this type of sensor are fast, but can be expensive. The CIS option sees the sensor sit close to whatever is being scanned for a good quality finish; whereas CMOS is known for being affordable.
