HI Stu, I still get spotting on 10-15% of custys and shops, Its difficult to see pics of spots so I have highlighted them on one of my windows that is Hphobic, taken from the inside, this is with 000tds rainwater water 12 hours after drying, the spots size outlines the actual spot from large to small.
Did them late yesterday, so it could be, The frames where painted this summer in and out and are in good nick, the bits hanging down are strings from the rolled up blind. But then I have the same prob for 6 years what ever the weather.That pic is also with an additive to reduce spotting. Just done another section of the same window with a special brush I have to do a side by side comparison- if I can get similar light conditions for the pic.
Just trying to help others so thanks for not riddiculing me.
if the glass only is cleaned and not touching the frames then the spots are still there.The tds readings are correct over a 5 year span.I have covered the window with pvc covers to try to prevent dust ingress but it makes no diff, its the glass surface thats a prob and also for maybe 30 other houses and shops I clean. The dried on spots are also still visible next time I do my round.
Hope this helps Stu