gritty eyes

[kieran]

so today we (cairngorm) had a bright hazy day. hill approx 2500' up, this sort of cloud cover.

i was wearing my julbo explorers which have a cat 2-4 polarised photochromic lens, brown tint, and side shields. depending on the light i'll switch between those and a pair of cebe strix, which are a 3-4 non-polarised lens with grey/neutral tint. also a fully-shielded frame.

tonight i have gritty and sore eyes. any recommendations for something darker or better than category 4?

[Beckmann AG]

Oakley, VR28?

[kieran]

thanks, i'll send them an email. ideally i want something polarised with less than 6% transmission. both the cebe and julbo lenses are 7-8% when fully darkened.

[Beckmann AG]

Not sure on the actual specs, so far as transmission etc. (Oakley used to have a chart) VR 28 has been the most effective for most of what I'll see over the course of a winter. As the mountain moves out of the shadows later in the season, I'll go for the Red Iridium, and then Black Iridium, but the black is too dark for any kind of flat light.

[OhD]

Goggles, and preferably no contact lenses. Soft contacts and frequent drops if you aren't up for Lasik but need correction. I don't think the human eye was evolved to go 30mph in cold, dry air and intense UV while being sprayed with ice crystals. I've never found sunglasses adequate for wind and glare, except for "glacier glasses" with the leather shields, and goggles are way more comfortable unless it's really warm. I know any number of folks who are cultivating pincuegulae - strongly correlated to UV exposure. They are kind of cute at first....

[kieran]

well the julbo explorers are glacier glasses, albeit with plastic side shields.

i get a good air seal from both the julbo and cebe glasses, and prefer not to wear goggles as i find they really impact my peripheral vision. i like my peripheral vision. ;)

[OhD]

Read up on sunglasses standards on Wikipedia, for a good start. Julbo claims no certification that I can find in a cursory browse through their website, nor do they explicitly claim to block any particular wavelengths to any stated degree. Cat. 3 to 4 doesn't seem to map to the EU EN 1836:2005 standard ratings. Julbo glasses may be perfectly fine, but they don't seem to want to say just how fine in any quantifiable terms.

A dark lens that doesn't filter UV can cause more harm than good, by causing your pupil to dilate and admit more UV into the eye (and also reduces visual acuity because of the large pupil).

I agree that peripheral vision is nice to have. Emphasis on the noun...

If you find more technical info on the Julbos, please pass it along. They do have quite a variety of pretty cool and comfortable-looking shades, and I'd be surprised if they don't have reasonably good UV protection, but your eyes feel gritty and sore. Knock-offs, perhaps? Know anyone at the local university who might have a spectrophotometer?

[kieran]

well they were store-bought, though how much that means these days is anyones guess.

oddly, in april and may this year i had no such problem with these glasses; right now our maximum sun altitude is 9°, and in may it would have been nearer 54°. will incidence angle be a contributing factor?

[OhD]

Could be. Sky light is polarized significantly only in the range of 60 - 120 degrees off the axis of the light ray from the sun. When the sun is high, that band is more nearly parallel to the horizon, so more of the sky in your normal field of view is emitting polarized light at you. When the sun is low in the sky, the polarization band is effective only in 120 degrees out of the 360 degree horizon. Light reflected off the ground is most strongly polarized at about 53 degrees off the incident angle, so when the sun is at 9 degrees, the reflected light is not so highly polarized. Therefore, the polarized lenses aren't doing you much good unless you are facing about 90 degrees from the sun - you are seeing pretty much the same light you'd see with plain filtered lenses, with perhaps a noticeably reduced amount of sparkly glitter off the snow.

The slopes there appear to be mostly North-sloping. I imaging riding the lifts you're getting the sun straight in the face in the morning, and lots of light reflected off the snow at a low angle. Even though it's going through a lot of air at that latitude, you're still getting nearly a double dose of the solar UV because of the reflection. I wonder, too, if the ozone layer is a little thinner than normal for this time of year? Might bear looking up. Are you getting more sunburned than normal?

Pretty intriguing countryside, based on a brief Google about the premises. Maybe I can get a winter visit there onto the joint bucket list. I haven't managed to get the Alps onto the joint list yet, so I'd say the chances are slim. Maybe enough Doc Martin will do the trick...

[kieran]

sunburned no, but sunstroke yes. my face is the only exposed skin and i wear SPF50+, but i still get sick at night after a day in the sun.

i went to the opticians today, they put my julbos through the transitions verification doodah. passed the uva/uvb tests, and showed 7.8% transmittance under full uv illumination. so it's not the glasses.

they did a full eye exam also and gave the all-clear, which was good.

[floBoot]

sunburned no, but sunstroke yes. my face is the only exposed skin and i wear SPF50+, but i still get sick at night after a day in the sun.

Are you a vampire? Perhaps get night vision goggles and snowboard at night:eplus2:

[crucible]

I am continually impressed by the depth and detail of the technical knowledge posessed by Bomber forum members- the info posted on UV standards had me going to Google and Wikipedia twice, as well as making my head hurt because of the need to retrieve long ago forgotten snippets of high school physics....

[Neil Gendzwill]

Goggles, and preferably no contact lenses.

Definitely mileage varies. I wear contacts and my trusty Oakley eye jackets so long as it's good light and not too cold. Don't like goggles but wear 'em in fog, flat light or cold.

[OhD]

I gave up on contacts finally when I found I was having to stop and scrub scratchy slime off them four of five times in a two-hour drive home. I had -10.5 diopters of myopia in my better eye, so the transition between contacts and glasses was too wierd to allow for just popping the infernal little devils out and putting on driving glasses. My optometrist steered me to Lasik when he felt it was mature enough, and sent me to Vancouver BC for the surgery, performed by one of the guys who was in on the development work. It took two visits with a 6-month rest between to let the eyeballs adjust to the thinner cornea. The first evening was kind of freaky, foggy, blurred vision, barely able to read a menu, and wearign fly-eye colanders to bed, but the next morning I could see the branches on the fir trees on the hills on the far side of English Bay! 8 years later I have a little myopia in one eye, a little astigmatism and (at 60) presbyopia, so I have to wear cheaters reading and doing close work, but I can board all day in a storm (in good-fitting Smith goggles) and drive home after with no drops or discomfort. I do use drops when it's dry, bright or allergy season (in Eastern WA) and have some progressive-lens glasses for driving after dusk - not required but certainly prudent. I feel really fortunate to have been born in a cetury of carving boards and computer-controlled ablative lasers - Like Paul Simon says: "These are days of miracles and wonder..."