I have a mid-2010 iMac 21.5" which has the built in iSight Camera. How does one adjust its zoom, up/down and lighting adjustments? If wondering, I tried 3rd party iGlasses program (which does zoom, lighting) but doesn't allow up/down adjustments. And, one must pay for this 3rd party program. Is there a way to change iSight camera setting for free??? thanks. .