The downstairs windows were original to the house and the double pane windows were no longer sealed. If you cleaned the windows inside and out there was still a film between the glass. I had the windows re-glazed with Low E double pane glass. You can't really show a picture of nice clean new glass so I just have a picture of the windows before showing the film between the glass that was clearly visible when the sun hit the glass in the mornings and afternoon.
Before:
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After:
Not shown but it is a really clear view.