Thankyou everyone for your informative and welcoming replies
Looks like the DGM is the G.O.
I had not heard of that filter before now so it was good to get your responses to make a decision. I had a look back over posts here in IIS and learnt a fair more about them.
Oh, and David and Mill, I surely will take up the offers to view, thankyou
Awaiting clear skies
derek