Natural sunlight over UVB?

[spookynoodle]

I'm housing both my blue tongues on UVB, but is it really necessary? I understand the benefits, but I take them out everyday for natural sunlight.
Is this better than artificial? I'm just wondering, I've been thinking about not replacing them when it's time to.
How many hours a week would I have to take them outside if I didn't use UVB?

 

[Sdaji]

They don't need UV at all. If you experiment (and I totally encourage you to!), you won't find any difference between natural, artificial, and none at all. It's possible that if you kept them outdoors full time you wouldn't need to give them supplements (that's something I'd be very careful about testing for fear of harming them), but if you're not doing that, and you are giving them supplements (which I consider effectively 100% essential), UV or no UV won't change anything.