I have a Canon EOS T3i 600D. When I use a Canon-branded lens (18-55mm), the camera works well. When I change to the Sigma macro 18-250mm and turn the camera on, I can hear a ringing noise, like ...
For a while my Sigma 18-50 f/2.8-4.5 lens has been shaking the viewfinder image once in a while. After asking a related question I settled for the explanation that it was the image stabilisation ...
I have a Sigma 610dg super flash that I wish to trigger with the TriggerTrap flash adapter (tt-fa1). Sadly I cannot make this work. I have tried two different TriggerTrap dongles but the flash never ...