Rebuild Blip!

Rebuild Blip ... well it would have been great if that's what it had said! 

However it was Rebuild Brookes Jetty; there has been a bit of a local kerfuffle over the council starting to demolish this decaying, unsafe jetty whilst the local residents want it restored. 
We wandered down along the walkway this morning; a mild morning but the sun was slow to come out. I came back and found dust spots all over every shot - argh!! I have a "puffer brush" but can anyone tell me whether it's OK to use those micro cloths that the optometrists supply (or would that risk scratching the filter?)
I have read that you should keep your sensor clean to prevent dust particles appearing on your shots but isn't this just dust on the outside of my lens filter? Any advice welcome!

A couple of extras to show the diversity of activity.