Put 24 oz. thawed frozen raspberries and their liquid, 3/4 cup sugar and 1/2 cup strained fresh lemon juice in a food processor and process until smooth. Press mixture through a fine sieve set over a bowl and discard seeds. Whisk 1 cup cranberry/raspberry juice into mixture. Transfer mixture to a measuring cup that has a spout and pour into 1/3- to 1/2-cup ice-pop molds and insert sticks. Freeze until firm, about 3 hours and up to 2 weeks. Unmold.