I put my impatiens and begonias, both shade lovers, under direct sunlight in a South facing window at this time of year, and they don't get burned. I doubt the indirect light is enough for the plants, even though it looks bright to our eyes, especially seedlings. Maybe when they are bigger?

Are you thinking that moving the seedlings might help you get a broader spectrum of light? Or that your fluorescents are not providing enough light? My opinion would be, if it's easy to move the seedlings, then the extra sunlight won't hurt, but it might not provide a noticeable benefit either. You're in zone 7; what is your weather like outside? We're going through a rainy spell here, but it's been in the 50's and sunny during the day here, so once the sun comes back out, I'm planning to move a lot of my seedlings outdoors during the day and in at night. So that's something you might consider if your problem is not enough lights/too many seedlings.

I was thinking I might get a broader spectrum of light. The tomato seedlings are getting a little leggy so I was trying to help them out. It's in the low 60's here during the day. I will set them outside. How long can I leave them in the direct sun?

I will set them outside. How long can I leave them in the direct sun?

Please don't! As sleepy said outdoors is fine but that doesn't mean direct sun. ;)

Direct sun will kill seedlings unless they have been hardened off first and that is a several-days-long process (you'll want to research 'how to harden off plants'). Outside in shade or dappled light for 1-2 hours, gradually increasing the time is fine. Protect them from wind as it too can kill them.

Also keep in mind that leggy plants isn't a spectrum problem - spectrum controls blooming and fruiting, not plant growth/height. It is an insufficient light problem so either more light or closer to the plants.

Dave