Loganberry Refresher

1/2 cup sugar
1/2 cup water
7 cups loganberries
2 cups orange juice
1/2 cup lemon juice
1 1/2 cups cold water

Combine sugar and water in a small saucepan, cook over medium high until sugar dissolves, stirring constantly; remove from heat and chill. Mash berries, then press through a strainer to remove seeds (optional). Combine berries with orange juice and lemon juice. Add sugar syrup and chill until very cold. Before serving, add cold water.