Calibrating a scanner is the process of adjusting its internal settings to improve image quality, accuracy and consistency. This should be done as part of regular maintenance on any scanner, even if you experience no noticeable problems with scanning. There are three key steps to calibrating a scanner: cleaning the surface of the scanner, aligning the optics, and running a calibration test.
1. Cleaning the scanner
The first step to properly calibrating a scanner is to clean the glass and frame of the scanner. A build-up of dust and scratches on the glass can decrease scanning accuracy and clarity. To clean the scanner, turn off the power and unplug it, then use a lint-free cloth lightly dampened with water or a special non-abrasive cleaner. Make sure not to use any cleaning solutions containing abrasives, as these can damage the glass.
2. Aligning the Scanner Optics
Once the scanner’s surface is clean, you should then align its optics. This is typically done through the scanner’s software, which will allow you to adjust the scanner’s focus and angle. When you’re making any adjustments, make sure to use a ruler to ensure accuracy.
3. Calibration Test
The last step in properly calibrating a scanner is to run a calibration test. For this, you can use a standard test image, such as a magazine page with a lot of detail, or a professional test pattern. Once you’ve found an appropriate test image, scan it at the highest dpi allowed by your scanner to let the scanner take a “snapshot” of it. Then, use software to compare the original test image to the scanned version. If there is a visible difference between the two—such as differences in tonality or color—then the scanner needs further calibration.
You may need to repeat the above steps multiple times in order to achieve the best possible result. You should also remember to periodically clean the scanner’s surface and alight its optical system, as dust and minor misalignments can cause decreased image quality over time. With regular maintenance, you can keep your scanner running at peak performance, resulting in superior scan quality.