The stylus tip radius influences what we see in surface texture measurement data. Since every tip is a little different, the resulting roughness values can be different even when you are trying to use the “same” radius. To make sure that the data from different instruments and styli are consistent we employ a “short wavelength” filter. In this video we will talk about how that filter’s cutoff is determined and what it means for your measurements. We also look at the common misconception that a larger radius stylus is more durable than a smaller one. It’s really not the case, and we will show you why.