The first concept that must be kept in mind when purchasing equipment are the limitations of what I label as "amateur equipment." I use this term when discussing peripherals so as to make the distinction between a drum scanner whose cost might be $30,000.00 and a flatbed scanner for $1,000 or under. The same rationale holds for output devices such as printers. Fortunately, digitizing tablets, which I will address later in this article, do not fall under the same price constraints.

It will be noticed that I mentioned purchasing a flat bed scanner. For good quality art work, I do not recommend a hand held scanner for it will not do the job correctly.

Unfortunately, in the computer field, there is a huge gulf between commercial items and those for home use. Thus, as stated earlier, the graphic artist who works commercially usually makes use of service bureaus and/or printers which use drum scanners and imagesetters. This makes the person who is working for pleasure or minimal profit dependent upon some equipment that is not meant for commercial use. This is important because it affects our choices in equipment; for example, how sophisticated must a scanner be? Should one purchase one with a bit depth of 36 or is a bit depth of 24 sufficient? In this case, what has to be borne in mind is the output device that will be used, ie., the printer. For those who are unsure of what I mean by bit depth, I will give a short definition. Each color red, green, and blue (RGB) have a color bit depth of 8 (8x3=24). If a scanning device has a bit depth of 30 or 36, then some of the bits of color can be theoretically discarded by the program. Thus, one might say, the more the merrier. Theoretically, that is true; but in actuality it is not. I have known of 30 bit scanners that gave better color renditions than did a 36 bit scanners. Even if a 36 bit scanner, for example, is excellent, the results from a home printer will not show this increase.

There are two parts to take into consideration when purchasing a scanner. These parts are the actual hardware or the scanner itself and the prescanning software program that comes with the scanner.

For basic use a 24 bit, single pass scanner that gives clear definition is adequate. Since I do not consider speed as important as quality, I will not discuss it. These flatbed scanners are scsi (SCUZZY) devices and come with their own cards. If one already has an scsi card and wants to add this scanner to the card, one should find out whether the scanner is compatible with the card. Unless one can install it oneself and is familiar with the often complicated process, I often advise people to pay a little more and order it through a local store that will check it out and configure it to one's system. These scanners can be purchased for under $500.00. Most of the major companies make these low end but perfectly adequate scanners. If one wants more speed and more bit depth, then a 30 bit scanner would probably accomplish this goal.

Another important hardware consideration is OPTICAL resolution. Optical resolution is built into the hardware while interpolated resolution is a matter of software. One should choose a scanner with a minimum optical resolution of 300 x 600. Unless one is scanning an image in line art, the output does not need to be greater than 150 lpi (lines per inch). Scanning at a ratio of 1:1, this corresponds to an input of 300 spi or ppi (samples per inch or pixels per inch.) Unfortunately, too often manufacturers and some authors refer to the input in terms of dpi. What needs to be remembered is that the image's resolution should be able to be 300 dpi or 150 lpi. Unless one is using line art, a final output of 150 lpi or 300 dpi is sufficient for most work including commercial output.

The next very important consideration when choosing a scanner is the PRESCANNING software. I believe this item is the least stressed in advertisements and the least understood.

The ability to manipulate the scan before it is actually finalized will give a better quality image than one for which major changes must be made after scanning. A good package should allow the user to set image size; image input and output resolution; manipulate color; choose the mode for scanning - line art, RGB, CMYK, or greyscale images; manipulate the image through the use of levels or a curve; control image brightness and contrast; and control noise (particles that look like dust). I purposely left out controlling sharpness because if one raises the level of sharpness, one all too often increases the noise level. I save this manipulation for my image editing package.

Another consideration when purchasing a scanner can be the choice of image editing package that comes with the scanner. However, this is not a quality choice but strictly a monetary choice. Often Adobe Photoshop or other image editing or painting packages are bundled with the scanner. If one is looking for such a package, purchasing even a "le" or light edition can be economically prudent.

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