If I want a really bright clamp lamp for crafting and painting, how many lumens, LEDs, watts or whatever it might be called do I need?

I want to buy a new clamp lamp with a long gooseneck and I'm not sure what brightness level I need. Since I went to OBI a few places away and they didn't have anything, and HOT doesn't have anything at all, and I don't want to wait a while until I can get to…