Thaw fish, if frozen; cut into 3x2-inch pieces. Rinse fish; pat dry with paper towels. Cover and refrigerate until needed.
For chips, cut the potatoes lengthwise into about 3/8-inch-wide wedges. Pat dry with paper towels. In a 3-quart saucepan or deep-fat fryer heat 2 inches of shortening or cooking oil to 375 degrees F. Fry potatoes, one-fourth at a time, for 4 to 6 minutes or until light brown. Remove potatoes and drain on paper towels. Sprinkle lightly with salt. Transfer potatoes to a wire rack on a baking sheet, arranging them in a single layer. Keep warm in a 300 degree F oven.
Meanwhile, for batter, in a medium mixing bowl combine flour, beer, eggs, baking powder, 1/2 teaspoon salt, and the pepper. Beat with a rotary beater or wire whisk until smooth. Dip fish into batter. Fry fish in the hot (375 degrees F) fat, one or two pieces at a time, until coating is golden brown and fish begins to flake when tested with a fork, turning once (about 3 to 4 minutes). Remove fish and drain on paper towels. Transfer fish to another baking sheet; keep warm in the 300 degree F oven while frying remaining fish. To serve, if desired, sprinkle coarse salt over fish and chips and serve with Tartar Sauce or vinegar.