Night Vision. How it works.

[Thrym]

i cant stand bright lights. In summer, im always squinting. and reflections of cars and puddles do it aswell gives me headaches

 

[ForgeCorvus]

i cant stand bright lights. In summer, im always squinting. and reflections of cars and puddles do it aswell gives me headaches

Are the headaches just like someone hammering a nail in just back of your eyes?

What you've described sounds just like the condition I have

Have you been to see an quack about it?

A few years ago (after a life time of having to nearly live in my sunglasses) I managed to get my doctor to refer me to a specialist (I had to get my eyes examined by an optician first), after looking at my eyes through one of those slit-lamps he said to me that there was no sign of disease.
He then asked if he could get some trainee doctors in to have a look !!
They all said the same thing, no disease, only one of them picked up on what he was trying to show them.
The back of my eye is unusally dark, this is caused by there being an above average number of rods there. This means that bright light can be painful and being out in it too long (without protection) gives me wanging headaches, however my night vision is awsome

So go check that you've not got anything wrong with your eyes (as you only get issued one set), and then take full advantage of being able to see when other folks can't (sneaking around the woods at larp events and not tripping over stuff every five steps in my case)

Crazyclimber, I had to put my sunnies on to look at those pictures, they're a bit bright

 

[Ogri the trog]

Thrym, Forgecorvus,
Thats ringing bells with me as well. I used to work permanent night shifts and I thought I was still in recovery from that - I wear sunglasses for virually every car journey except night time and get headaches from sitting in rooms with average lighting ( I prefer dimly lit places) - maybe its a little more involved than I had thought. I'll keep it in mind for my next visit to the Doc.

Thanx

Ogri the trog

 

[In Wood]

What a great thread, this has explained something to me.
When the Misses & I go winter camping, we will walk back from the local drinking establishment, Wasdale Inn for example, there is no artificial light at all once away from the pub and SHMBO can't see bu@@er all, her hand in front of her face but that's about it where as I hate her turning a torch on as I find I am able to see prety damn well, well enough to spot a tenner at the side of the road last time.

Last January I asked her not to use the torch at all as she would develope better night vision as we walked, she really was struggling even after about 20 mins I was asking her to tell me how far she could see and it was not far. She thought I was bullsh**ing so we did a test. I shut my eyes whilst she looked around with the torch and picked out items at various distances. She switched the torch off and asked me what was where and I could spot all but one a far distance off.

I also noticed this on a weks course in the bush with two other guys, they both needed torches at night where as I could walk from my hammock to camp, the lavi etc without any light other than the moon & stars without tripping over anything.:Wow:

I have not experienced head aches from bright lights but I must admit I will not go in bright sun without my shades on due to a scar on my eye ball that darkens if exposed to sun and shows up more prominently in my vision, I even wear them when swimming abroad.

Thanks guys this has enlightened me on this.:thinkerg:

 

[ForgeCorvus]

Well stuff me sideways....theres more of us about then I thought

We should form a club (the midnite lavi finders comglomerate )

 

[In Wood]

Hey Pablo, did this thread spark your latest blog?

As usual, another nice blog from your lovely site.

Now where the heck did i pitch my hammock?

 

[Galemys]

i cant stand bright lights. In summer, im always squinting. and reflections of cars and puddles do it aswell gives me headaches

There´s a book by Oliver Sacks, a neurologist, called `the island of the colourblind`. He visits a a small pacific island where most of the population lacks cones (and therefore colourvision) through genetic inbreeding. They suffer from the same symptoms and can only see in greytones. It ´s a very good read.

Cheers,

Tom

 

[irishlostboy]

those visual illusion things really melted my head!!!. the second one i thought was an animated image for a while.

i just got coloured filters for my head torch there recently. they are pretty cool. what is the advantages of green over red meant to be? i tend to leave the red one in.

 

[Toadflax]

Now I realise why it hacks you off so much at meets when people shine their head torches directly into you eyes.

Eric

I do what they taught us in basic training for when a flare goes off. If I'm in night vision mode, I instinctively shut one eye as soon as I get any hint of a light (to preserve the vision in that eye) and have a good look around with the other eye while the flare (or torch) lights up the ground. My head torch goes into red mode when it's first switched on, so I try to use that when I'm moving around in the dark and only use the white light modes if I really need better light.


Geoff

 

[bikething]

My head torch goes into red mode when it's first switched on, so I try to use that when I'm moving around in the dark and only use the white light modes if I really need better light.


Geoff

you have a headtorch with switchable colours ????

 

[Toadflax]

Splashed out on it last year. Primus PrimeLite CA - switches on to red, then has 4 different brightnesses of white, then flashing white. I like it.


Geoff

 

[bikething]

Splashed out on it last year. Primus PrimeLite CA - switches on to red, then has 4 different brightnesses of white, then flashing white. I like it.


Geoff

sounds like a well thought out idea - does the white go from dim to bright? - i've always thought the petzls do it the wrong way...

 

[shep]

i cant stand bright lights. In summer, im always squinting. and reflections of cars and puddles do it aswell gives me headaches

I sometimes get that. It's more likely if you have blue eyes as they have no pigment which absorbs some of the light.

 

[Toadflax]

sounds like a well thought out idea - does the white go from dim to bright? - i've always thought the petzls do it the wrong way...

It does, yes. There is one switch that turns the light on (to red - it always goes to red when it is first switched on), then a separate switch that cycles round the various light settings: red, dim white, white, bright white, very bright white, flashing white. The two brightest white settings are more of a pencil beam.


Geoff