« on: November 15, 2012, 07:03:43 PM »
I am new here and hope I am not jumping on someone else's thread but I am having problems with my Tamron SP 70-300 VC. Had it for 18 months and worked fine until recently coupled to a 550D. I mostly use for air shows like RAF Fairford so I have many photos of fast jets. The lens has always focussed well using single point focusing and I have extremely clear shots of planes at high speed so required fast focus on fast shutter speed. Recently the lens started hunting on all focusing conditions with the 550D. It was fine one outing and failed the next. I have cleaned all contacts and my other canon lenses work well with no focus issues. Is this a similar Tamron issue? Unfortunately I am not sure I have a 5 year guarantee. I'm not sure how I can find out. Any advice would be welcome.