How much light is needed?

[haney70]

I have 6 week old chicks. They are nearly fully feathered. I had to move them to the hen house last Wednesday because they were getting too big for my brooder box.
I had already stopped turning on the heat lamp since our night time lows here in Tennessee are in the mid to upper 50's.
They were pretty happy in their new accommodations until tonight. When I left them they stood at the door and cried and cried. They had food and fresh water. They had treats and snacks. I really think they wanted out.
I'm wondering if I need to turn a light bulb on in there during the day. Maybe they need more light? There are openings along the top and the hen house faces south east so they get some light in the mornings.
My plan was to keep them in there a couple more weeks and then start taking them out during the day and putting them up at night.
They are so small now and not quit fully feathered just yet. I don't want to start letting them out until they are a little bigger and I have them trained to follow me better.
So light bulb during the day? I'm working on installing a screened opening that will let in some more light and air. But maybe they need a bulb?
Please advise. THANKS!