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Scanning Speed

Scanning speed is another area of confusion for most customers. Although the speed is normally given in inches per second [ips], many large format vendors play little tricks to allow their scanners look better.

Here are some of the tricks we’ve found:

Scanning speed is rated at 2ips on a 36” wide scanner but the fine print reads:” Speed decreases if documents are wider than 24”
Scanning speed is only rated at 200dpi or 300dpi, no speed is specified at 600dpi. In many cases the real speed at 600dpi is more than four times slower than at 300 and the manufacturers are afraid to even mention those small numbers.
Scanning speed depends on the speed of the computer. Although this is somewhat true, one scanner vendor recently claimed that there is no computer available currently which would not slow down the rated speed of the scanner. If one looks at the speed ratings of Image Access scanners, it becomes clear that the computer is not to blame.
Draft mode, Turbo mode and other modes are used to specify speed. 400dpi turbo mode scans at 200*400dpi and therefore easily achieves the 200dpi speed but the customer is misled to think that this is something special, i.e turbo 400dpi mode.
Scanners might run at rated speeds for a couple of inches and then stop. After some time to clear the internal memory, they drive back a little and start scanning again.

Image Access scanners always scan at rated speeds -- regardless of the power of the computer -- because we are the only scanner vendor who does a full scan into the scanner’s memory at full speed, without any stops. Only the time between scanning and output are dependant on the transfer speed of the network and the computer. The only factors that determine scanning speed are resolution color depth and high quality/fast mode.

The rated speed of our current scanners under various conditions is shown in the following diagram. The WideTEK 36 is faster than the WideTEK 42/48 because it has three cameras compared to the four cameras in the 42/48 scanners.