Farming materials from HGEs and noticing there are "good" (not ignored) materials in the wreckage that are not displaying blips in the sensor display. The only way I can find them and designate them as targets is to do a Magellan with my ship until one of them randomly ends up in front of my ship and shows up in my HUD. I noticed because there were several more targets in my TARGETS panel than there were blips in the sensor display, even at close range.