Shred papaya and sprinkle in 1/2 cup of salt. Let it sit for about an hour and rinse. Using a cheese cloth squeeze out excess fluid. Set aside.
Place the vinegar, sugar, carrot, onion, pepper, ginger in a large saucepan and boil until the sugar is dissolve. Remove 1/2 cup of mixture.
Add shredded papaya into the vinegar mixture. Add the raisins and cook the papaya for about 5 more minutes while gently mixing so that sauce coat the papaya. Put the Atchara in a container and pour in left over vinegar mixture.
Let cool and refrigerate for 3 months. You can store it in the freezer also.
Before boiling, mix the vinegar and sugar slowly and see if it is according to your liking. Start with 1 cup vinegar and 1/4 cup of sugar and do taste test.