[Jeff Brimble]

Hydrophillic sheets perfect every time no dried spots.
Hphobic 1 non sheeting but dries OK
Hphobic 2  non sheeting droplets always dry into small white spots av of 8 per 4sq"

Looks like that glass is type 2, hard luck.

Try blading/scrim  as mentioned.
Maybe the pic but your brush looks manky ?

[Clear Vision]

Yes your right my brush is manky but the bristles are fine.

I have cleand this house with a brand new brush before and still the runs of spots.

Must be the type 2 windows