For digital holographic applications, we have studied the refocus criteria operating on the high-pass filtered and the nonfiltered reconstructed complex amplitudes (RCAs), respectively. A set of 10 criteria have been investigated for applications on phase, amplitude, and mixed objects in off-axis digital holography. Without filtering, the criteria always exhibit opposite behaviors for amplitude and phase objects and cannot work normally for mixed ones. With high-pass filtering on the RCAs, most of the criteria can be used regardless of the phase or amplitude nature of the objects without noises. But, in real applications with noises, they show different robustness. The investigations indicate that the criterion based on the integrated amplitude shows good exactitude and strong robustness, exhibiting a great potential in real applications, especially for multiobject systems.