In a medium bowl, combine the diced peaches with 1/2 cup of granulated sugar and the lemon juice. Stir gently to combine. Let the peaches macerate at room temperature for at least 30 minutes, or up to an hour, stirring occasionally. This helps draw out their natural juices and enhances their flavor.

Transfer about two-thirds of the macerated peaches (including their juices) to a blender or food processor. Pulse until you have a coarse puree, leaving some small peach bits for texture. If you prefer a smoother ice cream, blend until completely smooth. Reserve any remaining peach chunks to fold in later if desired.

In a large bowl, whisk together the very cold heavy cream, very cold whole milk, remaining 1/2 cup granulated sugar, vanilla extract, and salt until the sugar is dissolved. Make sure the mixture is well combined and smooth.

Stir the peach puree (and any reserved peach chunks, if using) into the cream mixture until thoroughly combined. Cover the bowl and refrigerate for at least 4 hours, or preferably overnight, to ensure the mixture is completely chilled. This is crucial for achieving the best ice cream texture.

Once the base is thoroughly chilled, pour it into your ice cream maker's frozen canister. Churn according to the manufacturer's instructions, typically for 20-30 minutes, until the ice cream is thick and resembles soft-serve consistency.

Transfer the soft ice cream to an airtight container. Press a piece of parchment paper or plastic wrap directly onto the surface of the ice cream to prevent ice crystals from forming. Freeze for at least 4-6 hours, or until firm, before serving. Enjoy your homemade peach ice cream!