Polarisation When to, when not?

[chip anderson]

I just sat through a "safety glass" course. In it we discussed "what you you give patient's with specific needs/occupations in sunglasses.
A lot of the suggestions were good but some were not possibly not quite so good. And while we many have discussed this before I thought It might be best if we tossed around and discussed when polarisation is and is not a good idea Below are some of the things I remember not from yesterday's course but from cumulative sources. And please don't miss-understand me, I love polarization and hope never to have sunglasses without it.

The not list first:

1) Airline pilots.
2) Search and rescue persons.
3) Sea plane pilots.
4) Snow skiers.
5) Golfers (My experience has been that pro and pro-wannabe's claim they can't read the green polarization, people playing for fun and relaxation much prefer polarized lense)

The Should have list:
1) Fishermen
2) Runners
3) Tennis players
4) Truck drivers
5) Motorcyclist
6) Water ski-ers
7) Any one not in the Should-not list who want's glare protection.

I'm sure I will have much more to add to this list once I have been up longer and my sinus cavities have drained. But what is your list of should/should nots for polarization?

[Barry Santini]

Seems like a complete list to me, Chip!

Barry

[DragonLensmanWV]

Yeah,my only modification would be to shorten the Should Have list to:
Everyone not on the Should Not Have list.

[For-Life]

Good list Chip.

I was always one of those who believed that in most cases, Polarization is not a needed option. I always felt that the first most important thing was getting a good pair on with protection and the tint. Then, I argue backside AR versus Polarization. I know that is not a popular comment, but this is what I have experienced. For instance, a few weeks ago, I went back to the old store and picked up a pair of new non-rx sunglasses to wear with my contacts. These were polarized (not the driving point behind the acquisition though), but had no backside AR. While they are tolerable, they do drive me nuts. I do not see as clear as I would like, because of the internal reflections.

I think of it like this. If I want to buy a HD tv, I have the choice of Plasma or LCD. Plasma, by far, has better picture. However, if you have glare in the room (such as a lamp or a window), those reflections on the screen will ruin the image. So in that case, it is better to get LCD.

[harry888]

Motorcycle riders have told me they prefer to have the glare off the road to judge distances.

Thats about the only addition I would have to list.

Harry

[Uncle Double]

I know motorcyclists that say they can't see water or ice on the road with polarized lenses......

[rbaker]

Attached is an FAA brochure on sunglasses for aviators.

[Uilleann]

Wow. What a complete load of goat droppings!

I fly. Have done for years. I know many, many, MANY pilots. I also know a whole mess of pilots and flight nurses with the two largest medical rotor/fixed wing transports in the state. I have never run across a single situation where my polarized suns have caused any form of danger or hindered my vision. Ever. Neither have I had a report of any kind from any of the pilots I know of the same. Ever.

To categorically state that a pilot should not use a polarized lens because it is in anyway unsafe is simply and completely WRONG. And yes - I'd LOVE to take the FAA's article writer to task on that one. The assertions made are just ridiculous.

I also ski. Will be going up again on Wed.

To say the same about skiers/boarders is also just as irresponsible. Amazingly, we have a lot of those here too. (2002 Winter Olympics came here for the snow after all!) And there are a huge number of them who prefer polarized suns. I do. There has never been an instance that I was unable to see ice. Ever. Trees, rocks and cliffs are another matter.

There will always be a particular set of circumstances that governs what will offer the best possible vision (and safety) for any given individual. But to use these sort of blanket lists and write off a given lens type outright without any actual knowledge of the patients environment or personal preference is NOT a wise course to tread.

Be careful - and more than anything else - BE THOROUGH. Ask what your patient wants and needs before jumping to any rash conclusions.

And remember...profiling works best for the LAPD. :shiner: D'Oh!!

[YrahG]

POLARIZATION

.

Polarized lenses are not recommended

for use in the aviation environment. While useful for blocking
reflected light from horizontal surfaces such as water or
snow, polarization can reduce or eliminate the visibility of
instruments that incorporate anti-glare filters. Polarized lenses
may also interfere with visibility through an aircraft windscreen
by enhancing striations in laminated materials and mask the
sparkle of light that reflects off shiny surfaces such as another
aircraft’s wing or windscreen, which can reduce the time a pilot
has to react in a “see-and-avoid” traffic situation.

That was from the FAA document, I think I will believe that one. My father used to say just because you've never been in a car accident doesn't mean you don't need a seat belt.

For Skiers I have a very good friend that hurt himself skiing and swears he couldn't see the ice, I am sure that's not a problem in the Olympics as their hills are well groomed, but on an opticians salary the hills I ski I would prefer to be sure I can see the reflections from ice as soon as possible rather that later.

[Uilleann]

That was from the FAA document, I think I will believe that one. My father used to say just because you've never been in a car accident doesn't mean you don't need a seat belt.

For Skiers I have a very good friend that hurt himself skiing and swears he couldn't see the ice, I am sure that's not a problem in the Olympics as their hills are well groomed, but on an opticians salary the hills I ski I would prefer to be sure I can see the reflections from ice as soon as possible rather that later.
[/LEFT]

Polarized lenses are not recommended for use in the aviation environment.
In this author's opinion.

While useful for blocking reflected light from horizontal surfaces such as water or snow, polarization can reduce or eliminate the visibility of instruments that incorporate anti-glare filters.
Except for the fact that most instrumentation does not use any of this "anti-glare filtration" that is mentioned. The use of LCD and digital instrumentation has been increasing for the past couple of decades, and almost all are fully compatible with polarized sun lenses - in fact, many are actually enhanced in color and contrast.

Polarized lenses may also interfere with visibility through an aircraft windscreen by enhancing striations in laminated materials and mask the sparkle of light that reflects off shiny surfaces such as another aircraft’s wing or windscreen, which can reduce the time a pilot has to react in a “see-and-avoid” traffic situation.
The author states "may". And in my experience, of many various civil and commercial aircraft windscreens, I have *never* seen an interference pattern, or darkening of vision through a windscreen. I also would never rely solely on the "sparkle of another aircraft's wing for traffic avoidance.

In aviation, no matter how well controlled the airspace may be, it is always the pilot's first responsibility to "see and avoid". If you're VFR in Class D, you're on your own more or less to do so. But even in the busiest Class B and C, though you may have the advantage of a controller calling out traffic direction and altitude, it is still up to the pilot. And it's not difficult to do - polarized suns or not.

There seems to be this strange myth that polarized suns will also somehow magically eliminate 100% of any hope of seeing reflected glare: (ice, shiny airplane parts, golf greens) and this simply does not happen. You can still see all of these things. If you don't believe it - try it for yourself. But whatever you do - DO NOT fit eyewear based solely on what you read from a manual or hear in a class somewhere. ALWAYS get as much information as you can, and whenever possible - try it yourself!

Flying is an absolute joy for many of us - I'd suggest you look into a 'discovery flight' at your local flight school. Ask them to take you up in the most advanced A/C they have - something with a lot of LCD in the dash. Then try those polar suns for yourself and see what YOU think.

And if anyone cares to try the ice argument in the snow - I'll see you at the top of Hidden Peak at Snowbird on Wednesday! :cheers:

[chip anderson]

I have pilots that fly wearing polarized lenses and are quite happy with that.
Now the "objections" that I have heard to this are:
1) Commercial pilots may have polarized windshields and a 90 degree rotation of the head could result in blackness.
2) Instruments may not be visible with same as some depth finders on boats are almost impossible to see with polarised lenses.
3) Those in amphibious planes supposedly gain some knowledge on landing from the glare on the water.
4) Snow pilots and skiers may not see glare from ice or water.
5) Skiers may not see glare from certian types of rocks.

Now personally I don't fly, ski, or do quite a few things so I don't have first hand experience with a lot of things. Even if I did there might be situations that I would not personally encounter. Sometimes you don't know if a thing is wrong until you make a mistake.

Chip

[Uncle Double]

Sometimes you don't know if a thing is wrong until you make a mistake.

Chip

I think that is the best reason to have fitting guidelines (or "blanket statements" for those who have limited knowledge of an activity) after all, who wants to make a mistrake?

[Uilleann]

I appreciate the opinions expressed here. I can also tell you from years of firsthand experience that in no situation I have seen, has a polarized lens done ANYthing except enhance vision. Also, remember that as the efficiency of a polarizing filter goes up, it's density also increases. Therefore, windscreens on jets (the only type that are laminated - in a process quite similar to your car windshield) being clear would have a very poor polarization effect. Secondly, what would the reason be for polarizing a windscreen? Glare reduction? If so, logically, the polarization film would be oriented horizontally - the same as your suns would be. So no black glass from a normal seated position. There is not a single situation I can think of that would require a polit to turn and maintain a head position of 90 degrees to the windscreen. At least not one that would also require them to be looking outside at the same time.

As for the ski/snow/ice debate. Look folks - Ice is ice. It is not made invisible in ANY WAY by wearing a polarized sun lens. None. You can still see it. It is still 'readable'. However, the intensity of obscuring glare is reduced. I actually find it much easier to see ice, and crusts with polar suns on.

My point is this - be aware that what you know - or think you know may not always be perfectly correct. Doubly so if you work on manuals for the FAA! The've made an entire government industry over getting it wrong for decades. Don't think so - ask any pilot! :hammer::D

[YrahG]

Sometimes you don't know if a thing is wrong until you make a mistake.

That's a very wise statement.

Ask them to take you up in the most advanced A/C they have - something with a lot of LCD in the dash. Then try those polar suns for yourself and see what YOU think.

I don't think my opinion would hold up in a court of law should something happen, although I see your point. The writer for whatever reason felt strongly enough to include it in the manual and the publisher felt strongly enough that the writers were competent professionals to have published the document, I am just an optician.

And if anyone cares to try the ice argument in the snow - I'll see you at the top of Hidden Peak at Snowbird on Wednesday!

I do know someone who did hurt themselves in a ski accident with polar suns on and it came first hand so although you feel strongly that it does not effect you terribly on the slopes, couldn't it be possible that someones else could be effected negatively on the slopes. Just a thought.

[Uilleann]

Quote:
Originally Posted by chip anderson
Sometimes you don't know if a thing is wrong until you make a mistake.

That's a very wise statement.

It's one thing to be cautious - and that is certainly wise and prudent. It's another entirely to base a decision entirely on limited and perhaps incorrect facts. Use your best judgment to try and differentiate the two. :cheers:

Quote:
Originally Posted by Uillean
Ask them to take you up in the most advanced A/C they have - something with a lot of LCD in the dash. Then try those polar suns for yourself and see what YOU think.

I don't think my opinion would hold up in a court of law should something happen, although I see your point. The writer for whatever reason felt strongly enough to include it in the manual and the publisher felt strongly enough that the writers were competent professionals to have published the document, I am just an optician.

The writer may well have never flown a plane in his life. Many of the technical documents put out under the auspice of the FAA have been written by "leading minds in the industry" meaning just about anyone BUT pilots. Who knows WHAT the writer was thinking, or feeling, or what other pressures may or may not have been present when this article was written. Speculation on the writers motivations or state of mind are, well....silly.

The fact remains that the assertions made in that paragraph do not hold up in any of the flight situations I am aware of. Nor have I heard of ANY difficulties, complaints and certainly no incursions either ground (far more common) or air that were ever in any way related to the pilot's choice of sunwear. I just don't buy it.

Quote:
Originally Posted by Uillean
And if anyone cares to try the ice argument in the snow - I'll see you at the top of Hidden Peak at Snowbird on Wednesday!

I do know someone who did hurt themselves in a ski accident with polar suns on and it came first hand so although you feel strongly that it does not effect you terribly on the slopes, couldn't it be possible that someones else could be effected negatively on the slopes. Just a thought.

I have an aunt who was nearly paralyzed from a rather horrific skiing accident some years ago as well. It sucks. No other words for it. Ice was the cause. She was in a non polarized goggle. Please believe me when I say you most certainly CAN still see ice and crust with a polar sun on.

I would be far more careful with my lens color and density on the slopes as they pertained to my overall visual quality as yes, you are correct that an improper lens choice can adversely affect one's perceptions on the mountain. But to state or imply that polarizing filters make ice utterly invisible or in any way impossible or even difficult to detect is simply false.

All the best :cheers:

[YrahG]

The writer may well have never flown a plane in his life. Many of the technical documents put out under the auspice of the FAA have been written by "leading minds in the industry" meaning just about anyone BUT pilots. Who knows WHAT the writer was thinking, or feeling, or what other pressures may or may not have been present when this article was written. Speculation on the writers motivations or state of mind are, well....silly.

The fact remains that the assertions made in that paragraph do not hold up in any of the flight situations I am aware of. Nor have I heard of ANY difficulties, complaints and certainly no incursions either ground (far more common) or air that were ever in any way related to the pilot's choice of sunwear. I just don't buy it.

Well I can't say I know what your credentials are compared to the writers other than you may be a pilot. I think the conviction you have toward the subject is admirable, but when you say what you state is fact and what the writer states is just an opinion it becomes hard to take you seriously on the subject. I guess this is one of those scenarios where it is up to each of us to formulate our own opinions. That being said i will take your considerations to heart.

[bob_f_aboc]

The author states "may". And in my experience, of many various civil and commercial aircraft windscreens, I have *never* seen an interference pattern, or darkening of vision through a windscreen. I also would never rely solely on the "sparkle of another aircraft's wing for traffic avoidance.

Is that MAY as in: Driving over hills on the wrong side of the road at 120 mph while intoxicated MAY result in bodily harm?

It only takes once!

[Uilleann]

Yes. I am a pilot. I also know many, many, MANY other pilots locally and across the country. Polar suns are GREAT when I fly, and are widely used by most of the pilots I know and work with. You're welcome to assume not one of us know exactly what works for us when we fly, though I'd caution against it. In fairness, it will likely cost you a patient (if it were me). I'm also a skier. I ski a wide variety of conditions at a number of locations across the state - always with polar suns. And as of yet - I haven't died, or ever been unable to read the mountain or see ice. I will never claim to be an expert in either field. What I will claim, and many of my friends, and patients will also - is that blanket statements made concerning the "safety" or perceived lack thereof pertaining to polarized sunwear in these situations simply doesn't hold up in the real-world situations we encounter while engaged in those activities.

There may be isolated instances where some effect may be noted, but hardly anything threatening to life or limb. And yes - I'd say the same on the witness stand in court. I hope that's helpful to some here. :cheers:

[chip anderson]

Surely Ullianne you wouldn't suggest that our government and it's various agencies would even think of passing needless regulations just to assert is authority would you? What's a bureaucrat supposed to do after all? They don't live in the real world you know and have to have those awful lobotomies before they can sign on with the government.

Chip

[sharpstick777]

I also have a lot of pilots as patients, including one who does water landings (in Seattle we have an actual water airline called Kenmore Air). In all case I warn them against Polarized lenses, and in all cases they prefer them. The instruments are brighter now so LCD screens can be read and they feel that despite the loss of sparkle of distant objects they can still objects farther and clearer in difficult light situations with Polarized lenses.

I think the fear is misplaced.

I have pilots that fly wearing polarized lenses and are quite happy with that.
Now the "objections" that I have heard to this are:
1) Commercial pilots may have polarized windshields and a 90 degree rotation of the head could result in blackness.
2) Instruments may not be visible with same as some depth finders on boats are almost impossible to see with polarised lenses.
3) Those in amphibious planes supposedly gain some knowledge on landing from the glare on the water.
4) Snow pilots and skiers may not see glare from ice or water.
5) Skiers may not see glare from certian types of rocks.

Now personally I don't fly, ski, or do quite a few things so I don't have first hand experience with a lot of things. Even if I did there might be situations that I would not personally encounter. Sometimes you don't know if a thing is wrong until you make a mistake.

Chip

[Uilleann]

I'm not sure if the LCD panels are necessarily much 'brighter' than they have been in the past, but one thing that does seem to be fairly consistent is that the polarized orientation of the screens is pretty consistently done in a horizontal plane - the same as polarized eyewear. This will give a sharper view of the panels to the pilot the same way it removes glare and reflections from the inside of a windshield when we drive.

As to the ski/ice argument. I was up yesterday. GORGEOUS day for spring skiing. Took the tram to the top of Hidden Peak at Snowbird - 11,000 ft MSL. Blazing sun. The south faces of Mineral Basin were super slushy, so didn't even try those. Stuck to the North and East faces of Peruvian Gulch and the upper runs of Gad Valley.

Overall, the snow conditions sucked - it was spring skiing after all. But there was a TON of sun, and a massive amount of glare. Conditions ranged from complete watery slushy crap now, to frozen ice in the bowls and shadows, to hard packed groomers that were a strange combination of ice and slush. I took three pair of suns up with me to compare all at once (two different polars and one non). My ski partner had two himself (one polar, one non).

At the end of the day, neither of us died. That was the best part! As far as seeing the slick vs. the squish, glare vs flat, there was no difficult whatsoever in determining ice with the polar suns, vs. non polar or goggles. In fact, we found that the brown or rose polar lenses gave us the best overall clarity and ability to read the runs vs. non polar or grey lenses.

I did take a pretty wild tumble on my first run, but I blame my own flabby frame, and weak quads...oh and the crap rental boots I was stuck with for the day!

So, for any who sell sunnies to skiers and/or pilots, my advice would be to ask them what they prefer. And if they have no idea, or have never tried polar, they may be well served in at least giving it a go for themselves.

Remember, glare is NOT in anyway eliminated with a polar sun. But it is brought to a level much more manageable for most of us. And it can, in fact, enhance visibility and perception of sheen in certain situations. Worth a second look for those who haven't before!

[EyeFitWell]

According to my Maui Jim rep, Golf Pro Magazine gave the MJ suns (all polar) a thumbs up for one of the best picks for golfers.