Scanners - Colors

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Scanners - Colors and Stuff

Colors And Stuff

-So, what makes the ole scanner see in color? Did you know that a scanner isn't so different from your dog? Yep it also should be neutered. No, not really. The scanner's CCD can only see in gray or voltages that are assumed in gray. Your scanner has to take three snapshots of your photo or document to figure out what the colors are this is done in red, green, blue. This means lot of work. The scanner will basically sit at one spot and take the three snapshots in 3 colors then only to make a building block of the colors for a individual pixel. This is getting real small folks. Not only this but by scanning to such a big degree we are looking at 16.7 million colors that you cant see anyway.

-Now what is used to see the colors? A light filter to limit the amount of light that is expected from a specific color or shine a light in that shade of color to the document. By doing this the scanner can get a great idea of what the color is of our photo's. Most scanners use a light filter for this.

-As mentioned before we have to pass over the document 3 times to get a idea of the colors that are on the image or document. There are three approaches to this, take 3 passes or one pass with alternate light or light filter. Most will do one pass actually and use a light filter.

-Three Passes, this is used mostly on flatbed scanners and will take three passes to get red, blue and green colors. Then with software we can patch all the passes together composite style for a accurate depiction.

-Alternate Light, the scanner alternates the light in red, blue, and green to compose the image or document. This is found mostly on handheld's and sheet fed scanners.

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