Flora

Hello everyone I recently purchased the Skywatcher Explorer 150 PDS with an EQ3 Synscan PRO Go-To Equatorial Mount with Aluminium Tripod. As I am a novice in the astronomy field, I have several questions. I'll start with one Can anyone explain to me, how a Crayfor focuser functions? I've attachhed it to the telescope, but I can't seem to make it focus (ironically!) even when I detach it from the telescope. Kind regards Flora