As the LHC injectors have to provide bright beams, all the potential sources of emittance blow-up must be eliminated. One such source arises from the mismatch of the betatron focusing at the interface of a transfer line with a circular machine. Measurements and corrections of this effect have been performed in the line downstream of the linac where space charge plays an important role and between the booster and the PS ring where four beams are recombined and have to be matched simultaneously
