Explaining the threshold - a vital setting for successful raster to vector conversion

Along with resolution, the threshold is the most important setting you need to choose when scanning a drawing for raster to vector conversion. Choosing the correct threshold can make the difference between raster to vector conversion success and failure.
 

Threshold too low

 
 
 
Choose a threshold that is too low, and parts of your drawing will be missing from the scan.

Threshold too high

 
 
 
Choose a threshold that is too high, and parts of your drawing will merge together.

In either event, valuable information is lost and you will not be able to produce a successful conversion.

What is the threshold?

Simple and adaptive thresholds

When do you set the threshold?

You normally set the threshold at the time of scanning, using your scanner's scanning software. You may also be able to set a threshold to turn grayscale images to black and white in your raster to vector conversion software.