Augmented-vision devices that we are developing to aid people with low vision (impaired vision) employ vision multiplexing- the simultaneous presentation of two different views to one or both eyes. This approach enables compensation for vision deficits without depriving the wearers of their normal views of the scene. Ideally, wearers would make use of the simultaneous views to alert them to potential mobility hazards, without a need to divide attention consciously. Inattentional blindness, the frequent inability to notice otherwise-obvious events in one scene while paying attention to another, overlapping, scene, works against that sort of augmentation, so we are investigating ways to mitigate it. In this study, we filtered the augmented view, creating cartoon-like representations, to make it easier to detect significant features in that view and to minimise interference with the normal view. We reproduced a classic inattentional blindness experiment to evaluate the effect, and found that, surprisingly, edge filtering had no detectable effect - positive or negative - on the noticing of unexpected events in the unattended scene. We then modified the experiment to determine if the inattentional blindness was because of the confusion of overlaid views or simply a matter of attention, and found the latter to be the case.