What you want to do is begin a hardening off process before you just stick a plant out from indoor to outdoors.
Find what the average last frost date is for your area.
On nice days, two to three weeks before, start taking the plant outside for a couple hours to begin with, paying attention to when the sunlight starts wilting the leaves, then bring it quickly back in to recuperate. This happens fairly quick the first time, because sunlight vs. HID has a pretty different intensity, so pay close attention the first couple times.
After things seem ok for a couple hours, increase that to a few, then half the day, then all day outside when it's nice.
Then whenever the average last frost date has passed for your area, and the plant is comfortable outside all day, go ahead and transplant outdoors, or pot up or whatever your plans are.
Good luck man!