I actually do not need "night Vision " if they will come into a lighted feeder, always been reluctant to leave it on as I was under the assumption they would avoid the corn.
If you can, get it up high and overhead. Light intensity and angle of incidence are pretty much what determines if hogs will react to it. It has been my experience...that hogs would MUCH rather walk under an area bathed in light (of their own volition in their own time) than have a light suddenly shone upon them.
Yes, they might 'hang up' on the periphery, but they almost always work their way in. I've also had much better results with Red light than green. But if the green is not too intense/bright...you might do fine with it.
Do everything you can to minimize 'shadows' (caused by placing the lights at low angles or too far away from the bait site).
Give it a try, what you are doing now...is not giving you the results you desire.
Now, before anyone jumps in here and tells me about their green/red/purple lights set on a fence post 10 yds from the feeder...and your hogs RUN to it. Yes, I know. I have some like that too. Those type of greedy, unwary hogs are NOT the ones we are worried about. Anyone will kill those. But pressured hogs...with a smart 'Lead Sow' won't go for it.
Spend a little time changing things up, experiment. You'll find the best combination for YOUR set up and will spook fewer hogs.