Lower it if you will (inflight) but I will never understand people who lower or keep lowered those shades on take-off and landing (especially landing). Don't you want to SEE your proximity to the ground as you are descending as well as be "prepared" for that hard-slam dunk (or not) when you actually land ? Good grief, to be moving at hundreds of miles per hour in a metal tube with no perception of this is maddening to me.