The main goal of the OPERA experiment is to detect the oscillation of vμ into vτ. The appearance of a vτ is identified by the decay signature of the short living τ lepton created in a charged current interaction of the vτ in the detector. However, vμ charged current interactions may produce charmed particles which can mimic the decay signature of the τ. In order to suppress this background it is crucial to identify the charge sign of the μ. Therefore a spectrometer with good spatial resolution and robust track reconstruction algorithms is needed. The OPERA detector has a magentic spectrometer consisting of drift tubes called Precision Tracker (PT) and resistive plate chambers (RPCs) in a magnetic field. An improved charge sign reconstruction algorithm is presented and tested on real data. Also, an alternative read-out scheme for drift tubes to remove ambiguities in the track reconstruction is shown.