🇬🇧 Guidescopes

To ensure that an astronomical mount remains precisely aligned with a set object, the tracking must be controlled. This control can be done using a small telescope mounted parallel to the main telescope. This small telescope is called a guidescope.

In contrast to a standard finder scope, guidescopes allow the attachment of a camera. This makes the tracking control process known as autoguiding possible. Guidescopes can also be used as finder scopes, though the necessary eyepiece is usually not included in the delivery.

The focus point of guidescopes is generally set so that cameras with a flange focal distance (back focus) of up to 2 cm can be used. For use as a finder scope, this means it is usually not possible to use a star diagonal or an erecting prism between the guidescope and the eyepiece.

Guidescopes are typically attached to the telescope's finder bracket ("finder shoe"); guidescope rings are used for this purpose.