Auto focus not working
Hi, I have a sigma 28-300mm for canon af, manual focus at all focal lengths works fine but not auto focus. when in auto focus mode and looking through the viewfinder i hear a whirring mechanical noise like it's trying to focus but just can't. is there anything i can do? thanks
Cameras - Sigma - 28-300mm f/3.5-6.3 DG Macro for Canon AF
Answers & Comments
Your Sigma 28-300mm doesn't have a HSM-motor as far as i know. When you switch it from MF to AF, you also have to disengage the manual focusing ring by pulling it towards the camera, or pushing it away from the camera. Using the AF without unlocking the manual focusing ring may damage the AF motor.
I hope this helps,
/Chris