how often and for how long, do you have to shine a light on such paint to get it to glow and how long does it keep glowing after you do so?
1-One second under a tactical lamp will give you an instant glow.
2-The glow time is relative to light conditions and eye adaptation, the glow can be rekindled almost instantaneously aanytime
On the flip side.....If you have plain gun sights without Glow-On, the answers are:
Pictures work better than words for me so here is a short video::scratchchin: