In a 3 litre saucepan, bring cranberries and apple juice to a boil. Reduce heat and simmer, uncovered, for 10 minutes. Press through a sieve; return to the pan. Also press the raspberries through the sieve; discard skins and seeds. Add to cranberry mixture; bring to a boil. Add sugar, lemon juice and cinnamon; remove from the heat. Cool 4 minutes. Stir 1 cup into 1.5 cups half and half. Return all to pan; bring to a gentle boil. Mix cornstarch with remaining half and half; stir into soup. Cook and stir for 2 minutes. Serve hot or chilled. Garnish with whipped cream and raspberries, if desired.