Pelco Developer Network (PDN)

Spectra HD Speed Profiles

This article is only for changing speed profiles via Web GUI and not through Pelco API.

By default, Sarix-based pan/tilt cameras have operated with a “bell”-shaped curve with regards to their velocity values. This means that the first ~65% of the speed values would result in very little movement, and as you increase the velocity value and approach maximum, the speed of camera movement increases exponentially.

As an example, if a camera’s max velocity for pan/tilt is 4000, velocity values of about 2600 or lower (approximately), will result in little pant/tilt movement. Movement will still occur; but will at a slower pace than the upper range of velocity values. As the velocity value for pan/tilt approaches maximum, the camera responds with faster and faster speeds until reaching top speed for pan/tilt.

The new speed profile that is available on Sarix cameras allows for an alternative that is less gradual and more linear. A translation takes place that converts the velocity value to a percentage of overall speed, and this in turn changes the camera’s rate of speed with respect to velocity. The result is faster responsiveness while performing activities like tracking people or vehicles. However, this alternate speed profile can be faster than users have been accustomed to when performing pan and tilt operations with a Pelco camera.


  • When changing between Linear and Default settings, previously existing application functionality may change. It is likely that previous development was completed with the assumption of the setting set to “Default”, and thusly the “bell” curve was in place. Changing the camera’s setting to “Linear” may cause a drastic change in pan/tilt speed in this case.
    • Using this option indicates an informed decision to alter the behavior of pan/tilt and should be done with this in mind!
    • Currently this setting can only be modified via the camera’s Web GUI. It cannot be modified using the Pelco API as of this writing.
    • This option is ONLY available for Spectra dome HD camera running firmware or later.

Taken from the Spectra HD Series Network Dome System S5220 Model product PDF:

A: Linear: Pan and tilt speeds operate in a linear fashion. Speeds start slowly and ramp up evenly to medium and then to fast speeds.

B: Default: Pan and tilt speeds operate in an exponential fashion. Speeds start very slowly and ramp up quickly to very fast speeds. The default setting is Default. 

Sample picture from Web GUI (option located under Imaging --> Positioning):

Speed Profiles