Simmer the cranberries: Combine the cranberries with 6 cups of the water in a large pot and bring to a simmer over medium heat. Cook until the berries split open and go soft, about 12 to 15 minutes.

Mash gently: Use a spoon to mash a portion of the softened berries against the side of the pot. This helps release more juice without breaking down the solids too much.

Strain through cheesecloth: Pour the hot mixture through a cheesecloth-lined strainer set over a large bowl. Let it drip undisturbed for 20 to 30 minutes, swirling the cloth once or twice.

Discard the pulp: Once the juice has fully drained and the pulp looks dry, discard the solids left in the cheesecloth. You should have about 4 cups of strained juice.

Combine with remaining water: Return the strained juice to a clean pot and stir in the remaining 2 cups of water. This brings the juice to a drinkable strength.

Add sugar and lemon juice: Stir in the granulated sugar and bottled lemon juice, along with the cinnamon stick and orange zest if using. The lemon juice keeps the acidity consistent for safe canning.

Heat the juice: Warm the mixture over medium heat to about 190°F, stirring occasionally until the sugar fully dissolves. Do not let it reach a rolling boil.

Sterilize the jars: While the juice heats, sterilize pint jars and lids in boiling water or a dishwasher's sanitize cycle. Keep the jars hot until ready to fill.

Fill the jars: Remove the cinnamon stick and orange zest, then ladle the hot juice into the hot jars, leaving 1/4 inch of headspace. Wipe the rims clean with a damp cloth.

Seal and process: Place the lids and rings on the jars, tightening just until snug. Process the jars in a boiling water bath for 15 minutes, keeping them fully submerged.

Cool and check seals: Remove the jars with tongs and let them cool undisturbed for 12 to 24 hours. Press the center of each lid; it should stay flat without flexing.

Label and store: Label each jar with the canning date and store sealed jars in a cool, dark pantry for up to 12 months.