I know prior to getting your eyes evaluated for DoDMERB they require you to go without contacts for at least 2 days prior; however, I do not possess a "good" pair (correct my vision to 20/20) of glasses and was wondering if this would prove a problem during my examination. Essentially, do they use a phoropter to determine if you're correctable to 20/20 (or better) or do they just rely on your glasses and a wall chart?