As 3D display technologies are becoming more and more common in commercial, everyday usage, a special type of 3D known as projection-based light field displays is emerging as well. While holding many key characteristics such as field of view or angular resolution, traditional image resolution also plays a major role in the overall determination of user experience, similarly to 2D displays. The paper investigates the perceivable differences between display resolutions, and presents the acceptability of resolution degradation should it be visible. A total of 20 test participants provided subjective assessment in a series of pair comparisons between 5 resolutions for various stimuli. Beyond mean scores, the results are presented in terms of score distribution in this analysis, separately for each and every stimulus.