For instance, a Dobsonian telescope might have an amplitude of 1 arcminute, a frequency of 5 Hertz, and a dampening time of 1 second. Wooden and aluminum truss Dobsonian telescopes typically have a frequency of several Hertz, that is, they vibrate back and forth several times a second. The relatively slow speed is due to large masses at some distance from the center of gravity. The frequency can be increased by making the upper end lighter, by making the mirror box lighter, and by shorting the tube. Increasing the frequency is desirable as the overall dampening time will often shorten.
Vibration is absorbed by the ground and by the mount itself.
A slightly soft surface such as grass or dirt will absorb vibration much better than concrete. But if the ground is too soft then it may act to amplify slow telescope vibrations. To promote absorption, sorbathane pads should be placed between the mount's feet and the ground. The frequency is lower with these mounts. In addition, these mounts suppress harmonics.