The OS/2 user is fortunate to have options for native OS/2 Scanning. Some hand scanners, many flat bed scanners and some digital cameras are supported. However from this point on it gets a bit complicated. Most scanners use a SCSI IO card. The better ones use an identifiably ADAPTEC card. Almost all of the scanner drivers listed below assume the ASPI (Adaptec SCSI Programming Interface?) Driver is present. Some of the supplied cards are unidentifiable i.e. Proprietary. The Logitech 256 gray scale hand scanner is the only proprietary board I know of that is supported under OS/2.
Which scanner you want depends on what you expect to input and what use you expect to make of the output. Are you going to copy printed material or film? Most scanners are designed for reflective originals, the light is reflected from an image on clear glass to a detector which creates a charge proportional to the brightness of the reflected light. Slide or transparent file requires a light source behind the scanned original. 33mm slide scanners are more expensive than flatbed scanners. Some flatbed scanners have an optional backlight attachment for scanning transparent media.
All scanners require an OS/2 specific scanner driver for the scanner model you are using. Windows Scanner Drivers will not work under Win/OS/2.
1. Software Needed
3. Scanning Photographs.
This is what most scanners are used for in the home environment. A gray scale scanner produces a bitmap of brightness values from 0 (black) to 156 (pure white). A color scanner produces essentially 3 bitmaps of brightness values ranging in value from 0 to 156, one red, one blue, and one green. The mixture of these three primary colors produces the colors of the image that your monitor displays or your printer prints. Your monitor displays RGB bitmaps directly, your Ink Jet printer translates (dithers) the RGB palette into a Cyan, Magenta, Yellow and Black (CMYK) palette. What you see is not what you will print, although with luck and effort you can get close. {If close isnÆt good enough better get an Apple, the only manufacturer that puts serious effort into this problem and why so many graphic artists are Mac users}.
Scanner resolution is more complicated that either monitor resolution or printer resolution because scanners do some interior image processing. There are multiple elements to the resolution issue, the sampling resolution of the detectors and the output resolution of the bitmap. Output resolution determines the image size and the file size. Graphic files can be huge. Scanning a large original at the highest capability of the scanner can crash OS/2 by generating a file larger than the available memory. Selecting the correct scanner resolution for a given image is strongly influenced by the resolution of the destination device - screen, ink jet printer or printing press. The resolution of the image that you are working with should match or be closely scaled to the capabilities of your intended output device.
4. Scanning Text for OCR.
This is a source of confusion for some. Scanners produce an image which is in itself no more editable than a photograph of a page of typing. To be able to bring the scanned text into a word processor you need an image application which supports Optical Character Recognition. This support is often available in a FAX program such as Fax Works Pro for OS/2. This is what I use - Scan the text to a TIFF. If you are going to send it as a FAX the file is ready to go. If you want to make a document out of it then drag and drop on Fax Works Pro. Save file as word processor file and clean it up in the word processor.
Most recent revision: May 31, 1999
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