2 Observing with optical instruments
Optical instruments such as telescopes and binoculars work primarily by using lenses or mirrors with large apertures to collect more light than can pass through the opening of the pupil in your eye. Having more light to work with makes it possible to see fainter objects and also to magnify the image.
In this section you will consider the different types of optical instruments used for astronomy and look at the different types of telescope, including the COAST telescope itself. You will also look at astronomical imaging cameras and sensors, which are used for their improved sensitivity over that of the human eye.