I've drawn several sets of objects, grouped some of them and toyed with different fill and stroke colors and opacity settings. Sometimes I used the eyedropper tool to copy colors from one object to another. Now I find that on some of the objects, I'm not able to restore the opacity to 100% even though the Control panel shows the opacity is set to 100%. I've tried ungrouping as well as copying and pasting onto a new document, but the problem persists. Any idea how I managed to do this and is it possible to get back to 100% opacity?