  A method for preparing a loophole-free four-photon Bell experiments which
requires a detection efficiency of 67% is proposed. It enables realistic
detection efficiencies of 75% at a visibility of 85%. Two type-II crystals each
down convert one correlated photon pair and we entangle one photon from one
pair with one photon from the other pair on a highly transparent beam splitter.
The entanglement selects two other conjugate photons into a Bell state. Wide
solid angles for the conjugate photons then enable us to collect close to 100%
of them. The cases when both photon pairs come from only one of the two
crystals are successfully taken into account. Hardy's equalities are discussed.
