I may be wrong here but I thought you couldn't fly with contacts. I'm wondering whether I have blind spots in my varifocals. I took a non pilot passenger up the other day and he spotted two (non-radar notified) a/c before I did. I'm OK with 'movement against the background' targets, it's the non moving ones I have trouble picking up and they are the ones that kill you.
I took off from a small non controlled airfield yesterday and came close enough to a helo while climbing through 500 ft which I presume was doing line inspections for me to go 'Bugger.'