I was told by my brother who owns his own neon shop that when you first use the bulbs that have mercury in them, you should leave them on for at last 30 minutes the first time. This will extend the life of the bulb. It's the mercury fumes that generates the brightness of the light. I've stocked up on the 3-way bulbs that I use in the living room, other than that I guess I'll have to go with the flow. As for the 'yellow' effect, my eye doctor told me as we age, our corneas tend to change from clear to a yellow-ish color lens.