Hair

Dog Hair. It seems, was causing my lens problem.  I'm very careful switching lenses too.  Little Dog's hair will be with us for years after she's gone!

At least I spotted it before I sent it off for fixing.  I'm still not entirely sure that's it because it was having trouble focusing on flying birds the other day too but this is unquestionably OK.  

Oh, and my bike ride gave me a good fix this afternoon too.