SUN GLASSES

John Galloway wrote, On 6/14/2013 7:08 AM:

Polarised sunglasses should genarally be expected to have
vertical polarization because the whole point about reducing
glare from water surfaces etc is that the light reflected of the
surface to the eye tends to be polarised horizontally.

On another topic - genuine question - do polarised lenses made
without a UV absorbing tint, and without a UV absorbing lens
material such as polycarbonate, reduce UV transmission more
than in proportion to the reduction in general light
transmission?

Your canopy filters out most of the UVB, as will almost every pair of
sunglasses, regardless of their tint or polarization. Plastic or glass
that passes significant amounts of UVB is "special" stuff that costs
more. UVA transmission is more variable, as it takes some effort to
filter it out, so if you want to block it, look for a pair that
specifically claims to do so.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

After trying a friend's Eagle Eyes (As seen on TV!!!), I found them to
improve detailed vision, especially spotting very thin dust devils. So I
bought a pair with built in readers.

They're great! I used them to take my wife for a ride in a friend's
DG-500m-22 and they were flawless. Yesterday, when I pulled down the canopy
of my LAK-17a, I found the screen of my CAI-302 to be totally black. At
first I thought it was due to the heat but, raising the glasses, I saw the
problem was with the misaligned polarization of the 302 screen with the
glasses.

I wonder if the glass in the 302 can be rotated 40-90 degrees...


"Eric Greenwell" wrote in message
...
John Galloway wrote, On 6/14/2013 7:08 AM:

Polarised sunglasses should genarally be expected to have
vertical polarization because the whole point about reducing
glare from water surfaces etc is that the light reflected of the
surface to the eye tends to be polarised horizontally.

On another topic - genuine question - do polarised lenses made
without a UV absorbing tint, and without a UV absorbing lens
material such as polycarbonate, reduce UV transmission more
than in proportion to the reduction in general light
transmission?

Your canopy filters out most of the UVB, as will almost every pair of
sunglasses, regardless of their tint or polarization. Plastic or glass
that passes significant amounts of UVB is "special" stuff that costs more.
UVA transmission is more variable, as it takes some effort to filter it
out, so if you want to block it, look for a pair that specifically claims
to do so.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email
me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl

On Sunday, June 16, 2013 9:42:52 AM UTC-7, Dan Marotta wrote:
After trying a friend's Eagle Eyes (As seen on TV!!!), I found them to

improve detailed vision, especially spotting very thin dust devils. So I

bought a pair with built in readers.



They're great! I used them to take my wife for a ride in a friend's

DG-500m-22 and they were flawless. Yesterday, when I pulled down the canopy

of my LAK-17a, I found the screen of my CAI-302 to be totally black. At

first I thought it was due to the heat but, raising the glasses, I saw the

problem was with the misaligned polarization of the 302 screen with the

glasses.



I wonder if the glass in the 302 can be rotated 40-90 degrees...





"Eric Greenwell" wrote in message

...

John Galloway wrote, On 6/14/2013 7:08 AM:



Polarised sunglasses should genarally be expected to have

vertical polarization because the whole point about reducing

glare from water surfaces etc is that the light reflected of the

surface to the eye tends to be polarised horizontally.



On another topic - genuine question - do polarised lenses made

without a UV absorbing tint, and without a UV absorbing lens

material such as polycarbonate, reduce UV transmission more

than in proportion to the reduction in general light

transmission?



Your canopy filters out most of the UVB, as will almost every pair of

sunglasses, regardless of their tint or polarization. Plastic or glass

that passes significant amounts of UVB is "special" stuff that costs more.

UVA transmission is more variable, as it takes some effort to filter it

out, so if you want to block it, look for a pair that specifically claims

to do so.



--

Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email

me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm

http://tinyurl.com/yb3xywl

No problem with my 302 with all polarized glasses I used. Either your glasses or your 302 polarized wrong.

Ramy

I always fly with my "Zoomies" binocular glasses (as seen on TV) https://www.buyzoomies.com/

Other gliders look 300% closer, so does the ground . . . it's a truly terrifying experience. I have no idea why a wear them but everyone else should as well.

bumper

On Monday, June 17, 2013 1:51:13 PM UTC-7, Ramy wrote:


No problem with my 302 with all polarized glasses I used. Either your glasses or your 302 polarized wrong.



Ramy

Some 302's had their polarization off by 90 degrees (I think they got a bad batch IIRC). When I bought my 302 in '03 screen blacked out with polarized glasses. Sent it in and they replaced the glass to fix this at no charge.

bumper

I don't know of any where to send mine now... I'll just use my older
non-polarized glasses and swap the Eagle Eyes to my car, hiking, and
kayaking.


"bumper" wrote in message
...
On Monday, June 17, 2013 1:51:13 PM UTC-7, Ramy wrote:


No problem with my 302 with all polarized glasses I used. Either your
glasses or your 302 polarized wrong.



Ramy

Some 302's had their polarization off by 90 degrees (I think they got a
bad batch IIRC). When I bought my 302 in '03 screen blacked out with
polarized glasses. Sent it in and they replaced the glass to fix this at
no charge.

bumper

Costa Del Mar or Revo non polarized!