Hard boil the eggs: place in a sauce pan and add cold water. Bring to a boil, then turn the heat down and lightly boil for 12 minutes. Run cold water into the saucepan to cool the eggs, remove most of the water, and add 2 or 3 handfuls of ice. Let cool 15 minutes then crack and peel the eggs.
Cut the hard boiled eggs in half lengthwise, and remove the yolk.
Place egg whites on a platter and the yolks in a small bowl.
Use a fork to mash the egg yolks into fine pieces.
Add the cream cheese, mayo, Dijon, red onion, chopped salmon, chopped capers, dill, salt, and lemon juice and stir to combine, (a rubber spatula works well for this)
Transfer this mixture to a quart sized plastic bag, and cut one of the corners, about 1/4 inch to create a piping bag.
Fill the egg halves to overflowing with the egg yolk mixture.
Cut the salmon as necessary to make approximately 1 in. by 1 1/2 in. squares and roll these up and press into the yolk.
Add a small sprig of fresh dill to each, and add 2 or 3 capers on each egg half.
Sprinkle some chopped onion on top to garnish.
Lightly pepper the eggs if desired.
Serve cold, store covered in the refrigerator.