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computerhakk · 10-26-2006, 07:30 AM

4. Terms to know

Terms that you should really look into when purchasing a scanner for the first time. These terms and it's information should be what aids you in your choice of picking this scanner over that other one.

DPI= (D)ots (P)er (I)nch:
The resolution rating that is given for scanners. It refers to the quality of image that the scanner can produce. The higher this rating, the better quality the image. This is determined by a horizontal rating by vertical rating (4800x9600). The first number is the actual optical scanning quality of the scanner in terms of dots per horizontal line. The second number is the number of mechanical steps the scanner motor makes in an inch. So the optical lens can scan up to 4800 dots horizontally, and the motor can make 9600 steps vertically in an inch.

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Scanner bit rate/color depth.
This refers to the number of colors that the scanner can use to interpret the image that it is scanning. For example, a 24-bit scanner can use over 16 million colors, while a 48-bit can use over 281 million colors. If this seems strange, it because this is an exponential scale. Each bit refers to the number of bits/3 (cyan, red, yellow) that the scanner can use to describe a color. For 24-bit each of the three colors uses 8 bits each, while a 48-bit can use up to 16 bits each. For those of you that are mathematicians, you must use permutations/combinations to actually mathematically add up the total possible colors available.

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Interpolation.
Also a factor of resolution where the scanner extrapolates what a plausible dot would be between two other dots. Example: Two known dots are blue, so the dot between them would also be blue, this usually means a higher resolution, but possibly less accurate image.

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10-26-2006, 07:30 AM	#5 (permalink)
computerhakk VIP Member Join Date: Aug 2005 Location: THOJhakk county Posts: 3,634	Terms to know 4. Terms to know Terms that you should really look into when purchasing a scanner for the first time. These terms and it's information should be what aids you in your choice of picking this scanner over that other one. DPI= (D)ots (P)er (I)nch: The resolution rating that is given for scanners. It refers to the quality of image that the scanner can produce. The higher this rating, the better quality the image. This is determined by a horizontal rating by vertical rating (4800x9600). The first number is the actual optical scanning quality of the scanner in terms of dots per horizontal line. The second number is the number of mechanical steps the scanner motor makes in an inch. So the optical lens can scan up to 4800 dots horizontally, and the motor can make 9600 steps vertically in an inch. . Scanner bit rate/color depth. This refers to the number of colors that the scanner can use to interpret the image that it is scanning. For example, a 24-bit scanner can use over 16 million colors, while a 48-bit can use over 281 million colors. If this seems strange, it because this is an exponential scale. Each bit refers to the number of bits/3 (cyan, red, yellow) that the scanner can use to describe a color. For 24-bit each of the three colors uses 8 bits each, while a 48-bit can use up to 16 bits each. For those of you that are mathematicians, you must use permutations/combinations to actually mathematically add up the total possible colors available. . Interpolation. Also a factor of resolution where the scanner extrapolates what a plausible dot would be between two other dots. Example: Two known dots are blue, so the dot between them would also be blue, this usually means a higher resolution, but possibly less accurate image. Top of page __________________ "Remember, wrong advice may be worse than no advice at all." ::COMPUTERHAKK::: Last edited by DCIScouts; 10-26-2006 at 07:51 AM.