in a large sauce pan combine simple syrup, cider, and raspberries
cook over medium heat until rasperries are soft enough to fall apart
remove from heat and add the pinch of salt, stir to throughly combine
pass the mixture through a fine mesh sieve or cheese cloth into a large bowl to strain out the seeds, pressing or squeezing to remove as much liquid and pulp as possible
chill throughly (or follow the instructions above if you don’t have an ice cream maker
add chilled puree to an ice cream maker and process according to manufacturer directions
put in a lidded freezer proof container (leaving room for expansioand freeze until solid enough to scoop- usually about 90 minutes to two hours
sorbet may need to soften out of the freezer for a few moments before scooping