Spraying at different air pressures and humidity levels can make a difference

and etch the metal for better adhesion of the sealer

but a darker shade may help the pearl effect come out more

and OE finishes

U-POL - Dolphin One Fill Premium Body Filler - Quart CHOOSE SIZE:QUART Spraying at different air pressuresDolphin One Fill is an All In One Premium Body Filler. One Fills intelligent micro sphere technology formula builds like body filler yet is super smooth and pinhole free like glaze so you can skip the glaze and get on to priming and painting in 20 minutes. Features: Industry leading adhesion to more substrates Sands to a super fine powder that wont clog your sandpaper Featheredges with no lifting or balling Outstanding vertical hold Technical Data