Originally Posted by
A37575
It is all great big myth. If passengers eyes need to be accustomed to the dim light outside the aircraft in an emergency evacuation - and this is the perceived reason for the dimming of cabin lights for take off and approach -then why are bright reading overhead lights permitted which are sure guaranteed to ruin the night vision of not only passengers in the area of bright lights (ever tried dozing at night when the clown next seat to you has his overhead reading lights blazing away?) - but the cabin staff are also affected as they walk up and down the cabin checking seat belts secured tray tables down etc at night.
Disagree there. If the lights are dimmed, then many passengers will benefit from improved night vision. If a few people have there reading lights on, that doesn't mean that it's not worth dimming the lights for everyone else. To say there's no point is a bit like throwing the baby out with the bathwater.
And of course, the elderly vision impaired (they wear glasses) passengers who need bright lights to read emergency instructions cards are immediately disadvantaged as dim cabin lights reduces their visual acuity to a degree they cannot even see the emergency exit signs ten rows away.
That's just a silly thing to say. If you have blind people on board should we not bother dimming the lights for everyone else because the two blind people won't benefit? There will always be people who won't benefit, choose to have their reading light on, smoke and have reduced night vision capability anyway, etc, etc. Other people will still benefit.
There is no factual medical basis for dimming the cabin lights in daylight or at night simply because of night vision reasons.
Just not true. Even 30 seconds of reduced lighting will greatly benefit your night vision. Although it is widely accepted that it will take up to 15 minutes or so before you reach the maximum benefit. Try it yourself by sitting in a brightly lit room and then turn the lights off. Within a minute you will make out objects that you couldn't see immediately after the lights went off. I don't know if these are the actual reasons that airlines decided or were told to dim their lights, but there is a benefit available to passengers who wish to avail of it.