The last three two-coat airbrush applications of well-shaken PollyScale flat finish (part number #F404106) thinned 10-to-15 percent with PollyScale thinner (#556008), have all produced small white spots on the dried cars. The spots were not noticeable while wet. They do not come off easily with thinner or with additional applications of the flat finish.
The spots do not look like dust or any other contaminant that adhered in between coats.
The paint solution was not filtered through a screen. Is this the problem?
Clinton (puzzled)