Boston-based Clear Ballot Group Inc. on Tuesday unveiled a new digital voting machine that could come in handy the next time election officials need to hold a recount. Unlike other machines that merely count the ink marks on paper ballots, the ClearCast voting machine scans and saves digital images of every ballot. These images can be inspected by officials to make sure votes were correctly counted. The system will also help election inspectors tally votes from improperly marked ballots. For example, a careless voter might circle a candidate’s name, instead of filling in the oval next to his name. With ClearCast, vote inspectors won’t have to physically inspect thousands of paper ballots to spot the blunder.