Eyesight at night

[Dizerens5]

I've often heard from older riders that they find it more difficult to ride at night. Now I'm 71 I find that too but put it down to brighter modern headlights of oncoming vehicles dazzling me. Maybe there's more to it. Here's a quote from the British semi-technical magazine "Astronomy Now":
"As you become older, the diameter of your dilated pupil shrinks. People in their thirties or younger have a pupil diameter of around 7mm, but this shrinks by a millimetre every two decades or so."
--This related to telescopes and binoculars: if you're an old guy there's no point in buying an instrument with a wide eyepiece because your smaller pupil opening won't see any more with one.
I would guess the same light loss goes for night time on the roads also.  

[Rob Valdez 79 R65]

All I know is I HATE those bright headlights!  Especially on trucks and truck-like cars that are another foot higher than the rest of the driving population.

But I'm just old & cranky.

It's even worse if it is raining.

But when you think about it, we weren't made for traveling any faster than a brisk walk, anyway.
And there are predators out at night.  Best to stay home.

[Ed Miller]

I'm being annoyed by my new Vector speedometer, as it's bright enough that it interferes with my sight of the road directly ahead of me, like when I'm trying to creep down my dirt driveway in the dark and in the rain.  Which is to say, most days, this time of year.  I need to adjust the angle a bit or see if it has a setting that's not so bright.

My night vision seems to be growing worse but I don't think I can retire on disability due to that.

[Barry]

I remember the figure of 7mm from my early interest in Astronomy and the  7 x 50 binoculars popular with astronomers because of the 7.1mm exit pupil they provided.

I didn't know about shrinking of the dilated pupil but I guess it's no surprise and goes hand in hand with the inability to focus at short distances  especially in poor light that also comes with age. Which is why I'm wearing reading glasses right now. So far I can get away with the weakest 1.0 dioptre lens most of the time but keep a pair with 1.5 dioptres in reserve for fine detail and put both pairs on at once to give 2.5 dioptres when I need to read something really tiny.

A bit of useless information - a 1 dioptre lens has a focal length of 1 metre, 2 diopters 0.5 metres, 3 dioptres 0.33 metres and so on.

And to answer your original question I  do find it more difficult riding at night than I can remember it ever being as a youngster. Don't get me started on modern bright headlights. Lights have 2 purposes:- to see with and to be seen by others. Super bright lights may be great to see with and while they can't be missed by other road user it's near impossible to judge speed and distance when you are being dazzled.  I believe many drivers use headlamps for "insurance purposes" in low light conditions when they have no need to see with them and in fact we would all see each other much better in terms of judging distance and speed if they used side lights or dim dip headlights instead. And the ultimate sin of the low IQ driver is using bright rear fog lights at the slightest hint of a mist so that you are dazzled and can then no longer judge when they are braking. One things for sure the lights are brighter than their brain - end of rant.

I think the original BMW head lamp on our bikes is not bad at all and must have seemed excellent in it's day. Back in the 70's stock headlamps could be pretty awful and I remember fitting a Cibie conversion to my 75 Triumph in order to improve things.

[montmil]

...Back in the 70's stock headlamps could be pretty awful and I remember fitting a Cibie conversion to my 75 Triumph in order to improve things.

Ah, youth... I remember it but only in bits and pieces. I'll be 64 this Thursday. That sucks. [smiley=nopity.gif]

My 1953 Triumph 500, sparked and lit by Lord Lucas, needed curb feelers to get me home many dark nights. Could have been my beer goggles. I forget. That's an advantage of aging...

The older I get, the faster I was. [smiley=2vrolijk_08.gif]

Monte

[Bob_Roller]

I've added auxiliary driving lights on the oilhead (PIAA 510) and PIAA 40 driving lights on the '81 R65 .

Definitely aids in night riding, which I do a lot of .

With out the additional lighting, my night vision isn't as great as it used to be and I'm 54, I really don't like riding without the auxiliary lighting on anymore .

[nhmaf]

Two of the more common contributing factors to night vision deterioration from age include:
1.  The lens in our eyes become stiffer and less flexible with age, and this reduces our ability to focus over wide range of focal distances (and thus need glasses for distance/near vision).
2.  Our corneas naturally become more opaque/milky as we age (in extreme cases - cataracts) and even just a slight increase in opacity is often sufficient to cause dispersion of single point light sources into a more broad/blinding pattern.
As my brother and I both have rare forms of glaucoma we are being treated for, I've learned alot about eyes over the past decade or so..

[Blackjack]

I've often heard from older riders that they find it more difficult to ride at night. Now I'm 71 I find that too but put it down to brighter modern headlights of oncoming vehicles dazzling me....... 

For us in the UK, there's also the EEC to thank. It's probably less of a problem in Kent as what I've seen of kent is fairly flat, but here in Bristol, since the standard for head light alignment changed from 1.6% down, to 1.2% down, anything coming the other way while you're both on an upslope is dazzling you.

Over the last few years, seems that everyone has taken to driving around with their front fog lights on because every one coming the other way is dazzling them (sheer genius....) and/or too fitting stupidly bright bulbs (which aren't legal for use on road vehicles).

The other problem here in the UK is that bulb ratings in the Construction and Use Regulations are expressed in watts. Watts is a measure of the current a light draws, not how bright it is, so while an incandescent bulb rated at 20 watts will have a certain candle power (which is a measure of how bright it is), a 20 watt LED array shining in your face is a different matter...

But, yeah, getting older isn't helping. I'm told that some vitamin supplements can help, but I can never remember which.

Here...

http://www.healthspan.co.uk/eye-health/

FWIW.

[dav]

It's even worse if it is raining.

Love riding in the rain & love riding at night, but put the two together with other traffic & it can be a bloody nightmare.

Hey Monte HAPPY BIRTHDAY for Thursday, 64 you say........

[Barry]

so while an incandescent bulb rated at 20 watts will have a certain candle power (which is a measure of how bright it is), a 20 watt LED array shining in your face is a different matter...
 

That's certainly a major part of the problem.

We have to remember that progress in the modern world means more is always better so before long we will all be driving around with enough candle power to turn night into day.

... only problem will be that nobody will be able to see damn thing.


Maybe as we get older we gain the wisdom to see that sometimes   ... less is more

[Lucky_Lou]

The introduction of Led and Hid is a problem, when im driving in my van (Transit) i cannot see the indicators/brake lights of the new Audi range of cars if i am closer than 30 ft, in traffic this is a real problem.Hid are totaly blinding unsafe for other road uses and illegal in most cases.
My eyes went AWOL a couple of years back for reading but my general eyesight is good i have one eye stronger than the other and my optician recommended a pair of tinted glasses for driving, they are great at night and not bad for shooting either.
Lou

[suecanada]

I have one heck of a time riding at night. I avoid it like the plague!! Changed for the worse as I got older. Now Monte and I are very close in age. I'll be 64 Jan. 3rd. Happy Birthday Monte for tomorrow!!!!
I wore contact lenses since 1969 and got onto monovision lenses which meant I had one long distance lense in one eye and the other eye was setup for closeup reading or reading the tankbag map. At night, the closeup lense takes over or is dominant so everything is blurry. My eye doctor says this has to do with the 'cones' and 'rods' in the eyes. What is happening I am not clear about but for anyone with contacts out there...do NOT use the monovision setup at night!!!!
I have changed over to wearing glasses (progressive lenses) for riding now and despite the fogging up, will stick to them from now on.

I have put driving halogens on LRB and have just ordered a set of LED driving lights for the Bonnie from Cree lights (Whitehorse Press motorcycle gear in Conway, NH). They have a reasonable price for a set as I found the Denalis and Clearwater LEDs to be pretty dear. I am at the stage where those lights are pretty well only for conspicuity during the day; not to light the road/ditch at night.

[Dizerens5]

Two years ago I had a cataract operation so I now have an artificial lens in one eye (the other is ok so far). It was brilliant, like having a new eye. But it doesn't have any effect on night vision. I've heard that while a normal lens filters out UV light the artificial one lets some UV through and it looks like silvery-blue colour. I've not yet found a UV source to try it out!

[balibeemer]

The problem is called presbyopia, or aging eye. It can, apparently be cured with laser surgery:
http://carefirst.staywellsolutionsonline.com/RelatedItems/1,2052

[Barry]

The problem is called presbyopia, or aging eye. It can, apparently be cured with laser surgery:

I knew it was called something like that but couldn't spell it.

I didn't do too bad being 52 or 53 before I realised I couldn't read in low light levels.

I've ridden home from school before now forgetting that I still had my low strength reading glasses on wondering why everthing was a slightly fuzzy.

Seems the laser treatment can cure most defects but perhaps there's no cure for ageing after all. A quote from that web page:-
 
Presbyopia or aging eye. The eye loses its ability to change focus because of the natural aging process. This usually occurs between ages 40 and 50. Refractive surgery cannot correct this problem. It can make distance vision clearer, but it may make near vision worse.