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Thread: Eyewear and Night Driving

  1. #26
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    High Contrast in Low Light

    I just remembered this, but many years ago when I was in Sacramento CA we had misrable "Tule Fog" in winter that reduced visibility to 600 and even 0 feet. One day it was so thick I had to drive with the car door open and look down at the barely visible dashed line. The end of my car hood was all I could barely see.

    more info here: http://en.wikipedia.org/wiki/Tule_fog

    I don't know why I did it, but one foggy day I put on my Revo Polarized sunglasses (long before the Luxmonster ruined them) and my range of visibility increased from 50 feet to about 250 ft (tested using a speed limit sign). I could not see great, but I could make out objects that were previously invisible, such things as bridges, intersections, roads and other cars... not exciting stuff but nice to see when you're driving.

    With the fog filtering about 70% of the sunlight, and my sunglasses reducing that light another 90%, I was only getting 3% of available light, but I still could see dramatically better with sunglasses than without. The net difference in contrast was startling.

    I tried out a Polar Brown A lens, adding yellow and red tint (orange) and throwing on a Blue Mirror coating on front, and backside A/R, with about 50% transmission. The result was amazing. In days I could see only a hundred feet without glasses I could see objects at almost 1000 feet with them.

    After I did a pair for a trucker, I ended up doing about 40 pairs of these for the California High Patrol and a bunch for other truckers (our office was near the Highway Patrol office) (its good lesson too on how powerful one referal can be).

    So in my case the reduction in total light was more than offset by the increase in contrast over distance due to the reduction of glare. Glare dropped at faster rate than the incoming light did, so contrast increased.

    Unfortunately there is no effective way to measure "glare" itself apart from ambient light, glare is inherantly subjective, so there is no way to formulate this mathmatically. But, if you have an extra frame around, you might try a pair next winter if you get fog where you live. They work great.

    Maybe glare has some type of threshold that if we reduce it enough contrast increases despite the net loss of total light. At least that's the theory I'm toying with.

    Sharpstick

  2. #27
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    As to Harry's comment on "good sunglasses" reducing bleaching (dimunition of visual purple) I seem to recall one of my previous employers (who was once for many years a B&L manager) quote B&L state that driving to work in the sun without good sunglasses could diminish acuity for 72 hours. However I did hear this second or more hand.
    As to the cornea flattening peripherally I suspect this is nature's devise to actually improve night vision (do not forget who designed the eye), of course when this was important in our early development the dangers and prey were usually a lot closer and slower than speeding automobiles.
    Other than when we hunt each other not much hunting (except for some Southern Deer and alligator hunters) is done at night these days.

    Chip

  3. #28
    Master OptiBoarder Joann Raytar's Avatar
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    Quote Originally Posted by sharpstick777 View Post
    Does anyone on this forum have difficulty driving at night themselves? Unfortunately I see really well in the dark (I actually prefer to drive at night because I can see so well). I am really interested in finding out if a digitally processed SV would be better than a standard stock lens.
    I do. My ride home at night is a dark winding road with no streetlights. Glare from headlights infront of me as well as behind make me nuts. But isn't directly from the lights; it's from light bouncing off my windows. This didn't used to bother at all years ago. On lit city streets - no problem.

    The fix, like Chip suggested, is a good dose of windex on windows and mirrors.

  4. #29
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    Quote Originally Posted by chip anderson View Post
    As to the cornea flattening peripherally I suspect this is nature's devise to actually improve night vision (do not forget who designed the eye),
    This is true, if we didn't have an aspheric cornea we'd have alot more people complaining of this problem.

    Anecdotally, I experience a quite a bit of spherical aberration and coma while driving (or even walking around) in the dark while wearing my specs. However, while wearing my purevision contact lenses, its almost entirely diminished, I believe b/c of the aspheric optics. When I wore the B&L Softlens, my night vision was even worse than it was with glasses, but I believe the addition of asphericity really does help.

  5. #30
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    prescribing for night / illumination control

    We have an instrument that can determine the effects of illumination and filters. The results we achieve would shock most optometrists.
    In many cases illumination control has more of an effect than the Rx (and the Rx can change significantly in differing illuminations!!! A range of around 3D +/- is found. The Rx prescribed is nothing like as accurate as most optometrists would like to believe)

  6. #31
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    My Night driving glasses

    As a keen Amateur Astronomer and frequent night driver myself I may summarize in order of importance or effectivness how I feel about this:

    1) Clean your windshield ( Outside AND inside ) and keep your glasses
    perfectly clean.

    2) AR will help to reduce glare from cars coming from behind or as they
    overtake (internal reflections).

    If this does not help then consider

    3) Night myopia affects a reasonable part of the male population, i.e.
    the impossibility to focus correctly due to low or missing signal contrast (sometimes also due to too much consumption of luiquid toxins...but that's a completely different story).
    Changing the prescription by 1/2 to 3/4 dpt. as suggested is then recommended, I myself (anisometric mild myopia) use a change of 3/4 dpt. for pinpoint stargazing (Mineral lens, Super AR).

    4) The wide dilated pupile brings out the worst aberrations of our one lens
    optical system eye. We know that binoculars with 3mm exit pupil
    produce the perceived sharpest image, as this 3mm aperture seems
    the best crossover between light input to the eye and optical errors increasing with aperture. The image quality of a 7mmm exit pupil binocular used fully dilated is a desaster, no resolution, no focus, and it's NOT the Binoculars.
    Therefor a gentle blue blocker i.e. yellow tint will be perceived beneficial to absorb those violett blue halos around any light source coming in sight at night.
    BTW, have you ever tried to focus at night onto a blue LED advert or
    display ?

    Clear skies and drive safely

    Georg
    ex Chairman of ASSA
    The Astronomical Association of Southern Africa
    Cape Town

    Better Best than Biggest

  7. #32
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    Blue Jumper Blue blocking lenses for driving................

    Quote Originally Posted by DoubleD View Post
    Too often I see recommendations of blue-blocking (yellow) tints, but strongly disagree that they really help in extreme low light.
    Slight yellowish orange color. Can be tinted over to appear to be amber, brown, chocolate brown and dark green.

    Edward Land, the inventor of Polaroid filters, came up with a theory that if one would use a filter that would block a certain color, that after a while of looking through it, the brain would compensate it and a person would actually see the color again that was blocked.

    Having been involved with blue blocking colors since the early 1980s and having changed the earlier version to a much lighter system than the older first and version, having worn them in all conditions from boating to driving, from sunny to foggy and dark conditions, I can certify that Edward Land's theory is actually working and true. Depending on the individual, the re-appearance to the seeing of the cut out blue light can last 10 minutes to in my own case a few seconds.

    Dr. Peter Wilkinson, an optical scientist in the UK recently made a study on the use of blue blockers for one of the major optical corporations who intends to market more blue blocking lenses in the near future.

    In my own experience I have for many years much more appreciated the blue blocker lens versus Polaroid lenses. You have a much better vision in hazy and semi dark condition, you see enhanced colors against a sunset on the water or the road.

    By being a pre, and now a post cataract patient, on both sides of the surgery the blue blocking lenses were a tremendous help to provide the needed comfort and good vision needed.

    However when it gets dark on the road, I check into a motel, and go back on the road by four am........................and funny enough the dark conditions after a good night's sleep are not there anymore and the 2 to 3 hours to day break are easy to drive without any special visual help.
    Chris Ryser
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    http://optochemicals.com............................. http://arcoatings.com

  8. #33
    ATO Member HarryChiling's Avatar
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    I don't know how blue blockers would be of any help at all, in night driving conditions the rods are providing the image to the brain, the rods are more sensitive to the greenish blue range so a blue blocker could potentially be harmfull in night driving situations, right? Look up Purkinje (sp?).

    Here's another suggestion what if lens designs were optimized for scotopic vision. For example the index given for reference wavelegth of 500nm instead of the 550nm we use and the designs why not be designed to be optimal for that particular wavelegth? This could be a nigh drivign lens.
    Last edited by HarryChiling; 04-27-2009 at 11:08 AM.
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  9. #34
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    Redhot Jumper

    Harry you are right......................I do not use them at night, I keep my eyes closed and dream something nice.
    Chris Ryser
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    http://optochemicals.com............................. http://arcoatings.com

  10. #35
    sub specie aeternitatis Pete Hanlin's Avatar
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    We don't dismiss these poly patients as nut cases, nor do we send them down the road explaining there is nothing we can do. They have not heard anything bad about poly in the media (some don't even know they are wearing poly) so they are not affected by advertising by the Trivex department at PPG.

    I think there is a danger in applying a median of optical behavior to all patients, and dismissing the one's that don't conform to our mathematical precepts. We don't do this with poly (I hope not) and I hope we don't do it with our patients with night driving issues. We just need more tools in our tool box.

    I didn't mean to imply that patient complaints/symptoms should be dismissed lightly... However, prior to life here at Essilor I probably dispensed well over 1,000 pair of polycarbonate lenses (its about all I dispensed for a couple years) and I could count on one hand the number of non-adapts I could attribute to material issues.

    However, I've had practitioners come up to me at conferences who have claimed to have poly non-adapts of up to 40% (one very solid OD with whom I used to work claimed close to this figure). So, it has always mystified me that some practitioners can dispense poly all day without encountering problems- while others routinely encounter problems. I'm not suggesting this has any relationship to the skill of the practitioner either- I know of some splendid opticians who report problems with poly.

    Personally, when I was a -4.75 I could see color fringing with polycarbonate (peripherally), but was never annoyed by it (although we've already established I a non-discriminating in my vision :^).

    As for polishing swirls, they are capable of producing all kinds of symptoms. One of the first questions I ask about poly non-adapts regards whether the lenses were SF or finished. Problems with finished SV poly product should be pretty rare.

    Regarding patients who defy the odds (and even logic), one thing my involvement with clinical studies has impressed on me is the human visual system is very complex- each individual has his/her own perceptions of virtually any optical lens... so anything is possible!

  11. #36
    ATO Member HarryChiling's Avatar
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    Quote Originally Posted by Pete Hanlin View Post
    We don't dismiss these poly patients as nut cases, nor do we send them down the road explaining there is nothing we can do. They have not heard anything bad about poly in the media (some don't even know they are wearing poly) so they are not affected by advertising by the Trivex department at PPG.

    I think there is a danger in applying a median of optical behavior to all patients, and dismissing the one's that don't conform to our mathematical precepts. We don't do this with poly (I hope not) and I hope we don't do it with our patients with night driving issues. We just need more tools in our tool box.
    I didn't mean to imply that patient complaints/symptoms should be dismissed lightly... However, prior to life here at Essilor I probably dispensed well over 1,000 pair of polycarbonate lenses (its about all I dispensed for a couple years) and I could count on one hand the number of non-adapts I could attribute to material issues.

    However, I've had practitioners come up to me at conferences who have claimed to have poly non-adapts of up to 40% (one very solid OD with whom I used to work claimed close to this figure). So, it has always mystified me that some practitioners can dispense poly all day without encountering problems- while others routinely encounter problems. I'm not suggesting this has any relationship to the skill of the practitioner either- I know of some splendid opticians who report problems with poly.

    Personally, when I was a -4.75 I could see color fringing with polycarbonate (peripherally), but was never annoyed by it (although we've already established I a non-discriminating in my vision :^).

    As for polishing swirls, they are capable of producing all kinds of symptoms. One of the first questions I ask about poly non-adapts regards whether the lenses were SF or finished. Problems with finished SV poly product should be pretty rare.

    Regarding patients who defy the odds (and even logic), one thing my involvement with clinical studies has impressed on me is the human visual system is very complex- each individual has his/her own perceptions of virtually any optical lens... so anything is possible!
    Pete,

    I see more poly issues on PAL's and FT's than SV I could dispense SV all day long and like you said count on my one hand the number of people that have truly been bothered to the point they won't wear poly, but in PAL's and FT's, reading is done by looking at a portion of a lens that is a distance away from the optical center. For a while I thought it was the design and I would change patients and sometimes it would be better other times it was still a problem. Then I started to change them into the same design different material and most cases were fine with the better material (AO Compact from a Poly to a 1.60) the amount of prism thinning will also have something to do with it.
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  12. #37
    ATO Member HarryChiling's Avatar
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    Oh and Pete your presentation on sunwear and the drivers reaction time:

    300 miliseconds amounts to 22ft at 50mph not 23ft, great stuff though. ;):D
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  13. #38
    sub specie aeternitatis Pete Hanlin's Avatar
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    I see more poly issues on PAL's and FT's than SV I could dispense SV all day long and like you said count on my one hand the number of people that have truly been bothered to the point they won't wear poly, but in PAL's and FT's, reading is done by looking at a portion of a lens that is a distance away from the optical center... I started to change them into the same design different material and most cases were fine with the better material (AO Compact from a Poly to a 1.60) the amount of prism thinning will also have something to do with it.
    I would suggest the surface quality might have played a role as well. Those SV jobs are probably mostly cast product, so the surface quality is very high. Poly is a great material- when processed correctly. However, it is a thermoplastic material (most ophthalmic substrates are thermocure materials) which creates processing challenges (plus, it breaks down polish at a much faster rate than other materials).

    Oh and Pete your presentation on sunwear and the drivers reaction time:
    300 miliseconds amounts to 22ft at 50mph not 23ft, great stuff though.

    Ah, were you at the meeting in Nashville? The precise decrease in reaction time was 330 milliseconds (I think I rounded down to 300). I don't know if that would change the distance traveled- to be honest I just took the numbers provided by the clinical site without bothering to check their math on that one (polarized isn't my main area on the tech team- I mostly deal with PAL design). I had to rush to the airport right after speaking- so I never did get a feel for how that presentation went...

  14. #39
    ATO Member HarryChiling's Avatar
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    Quote Originally Posted by Pete Hanlin View Post
    I see more poly issues on PAL's and FT's than SV I could dispense SV all day long and like you said count on my one hand the number of people that have truly been bothered to the point they won't wear poly, but in PAL's and FT's, reading is done by looking at a portion of a lens that is a distance away from the optical center... I started to change them into the same design different material and most cases were fine with the better material (AO Compact from a Poly to a 1.60) the amount of prism thinning will also have something to do with it.
    I would suggest the surface quality might have played a role as well. Those SV jobs are probably mostly cast product, so the surface quality is very high. Poly is a great material- when processed correctly. However, it is a thermoplastic material (most ophthalmic substrates are thermocure materials) which creates processing challenges (plus, it breaks down polish at a much faster rate than other materials).

    Oh and Pete your presentation on sunwear and the drivers reaction time:
    300 miliseconds amounts to 22ft at 50mph not 23ft, great stuff though.
    Ah, were you at the meeting in Nashville? The precise decrease in reaction time was 330 milliseconds (I think I rounded down to 300). I don't know if that would change the distance traveled- to be honest I just took the numbers provided by the clinical site without bothering to check their math on that one (polarized isn't my main area on the tech team- I mostly deal with PAL design). I had to rush to the airport right after speaking- so I never did get a feel for how that presentation went...
    330 is 24ft, I'll stop now. No I wasn't there but I just got a flyer in our shipment today and I saw your name on it and the mention of the driving simulator and was peaked. Apparentyl they recorded on DVD so I'll have it soon enough, can't wait. The flyer sent hade real substance to it though which leads me to believe that it is going to be interesting so I'm a bit anxious to get watch it, I'll let you now when I do.
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  15. #40
    Eyes eastward... Uilleann's Avatar
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    As an interesting (and I hope not too far of a tangent) thought, it's been on my mind recently the concept of this 'tint for night driving' thing.

    I would challenge that for probably 99.9% of humans, that we would actually be completely unable to reliably and consistently either:

    A. Tell the difference between a completely clear lens, vs a 10 % tint while wearing a given lens - especially at night, or in a dim lighting situation..

    &

    B. Actually tell what color the tint really is - especially at night, or in a dim lighting situation.

    (I'm assuming non-A/R lenses for the purpose of simplicity here, just actual perception of tint density and color)


    There is so little difference, and with the lower ambient light available in that setting, I honestly wonder how many of us could actually DO it. Even if we knew what we were looking for. I seriously doubt I could, and I tend to be fairly particular about my lenses as a rule.

    Just a random thought, and this thread has been great so I wanted to make sure it didn't drop off the radar too soon here! :cheers:

  16. #41
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    Quote Originally Posted by sharpstick777 View Post
    I just remembered this, but many years ago when I was in Sacramento CA we had misrable "Tule Fog" in winter that reduced visibility to 600 and even 0 feet.
    I tried out a Polar Brown A lens, adding yellow and red tint (orange) and throwing on a Blue Mirror coating on front, and backside A/R, with about 50% transmission. The result was amazing. In days I could see only a hundred feet without glasses I could see objects at almost 1000 feet with them.

    Sharpstick
    Quote Originally Posted by Chris Ryser View Post
    Slight yellowish orange color. Can be tinted over to appear to be amber, brown, chocolate brown and dark green.
    In my own experience I have for many years much more appreciated the blue blocker lens versus Polaroid lenses. You have a much better vision in hazy and semi dark condition, you see enhanced colors against a sunset on the water or the road.
    Sharpstick and Chris-could both of you discuss how the good and bad characteristics of the lenses you mention relate to color vs. polarization? Chris, you say you prefer blueblocker to polar, but is that because you can't get the color you want in polar, or because the polarization itself causes problems? Sharpstick, if you did the same color and coat in a non-polar lens, would you get the same good result?

  17. #42
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    Night driving with yellow lenses, myths and facts

    There seems no universal appliable solution to this endless sometimes emotional subject. You could compare it to the effectivness of any medicine: 1/2 of the effect is in the medicine prescribed and 1/2 in believing the GP that it will work. If a customer "feels" to see & drive better at night with a yellow, AR coated lens, we should not dismiss this. There are people who can see the position of Jupiters Galilean moons with unaided eyes, most folk have to use binoculars and will dispute this, but eyes are different.

    Let's look at facts rather.
    A shoothers yellow lens with a state-of-the-art AR (for example purpose http://www.vssunglasses.com/ShopOnli..._140-3031.aspx ) cut's in below 500 nm and is therefor hardly affecting the weighted visual Transmission V (lambda) or the Color balance.
    With 83% T(vis) a lens like this is qualified for night driving use as per EN ISO standard.

    BTW, I am not talking about blue blockers which cut Transmission at about 600nm downwards and should not be used or night driving.

    Georg Mayer

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  18. #43
    Eyes eastward... Uilleann's Avatar
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    Quote Originally Posted by Georg Mayer View Post
    ...There are people who can see the position of Jupiters Galilean moons with unaided eyes, most folk have to use binoculars and will dispute this, but eyes are different...
    Wow, now THAT one I would like to see proven! LOL I also know people who 'know they can fly' when on acid. Again...I ask them to prove it! ;):hammer::cheers:

  19. #44
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    Night Vision and resolution, given a perfect set of eyes

    I don't want to deviate off the subject, so, here's a link to Wikepedia:

    http://en.wikipedia.org/wiki/Galilean_moons

    chapter visibility. Only genuine optics, no acid ... ;-)

    Georg

    Better Best than Biggest

  20. #45
    ArielJG
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    Transition DriveWear, Helps me at night.

    Well all I know is that, at night I love my Transition DriveWear, It dose help my eyes from the Xenon light's that the new car's have today.
    I love it for the night driving.

  21. #46
    ATO Member HarryChiling's Avatar
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    Quote Originally Posted by ArielJG View Post
    Well all I know is that, at night I love my Transition DriveWear, It dose help my eyes from the Xenon light's that the new car's have today.
    I love it for the night driving.
    That's interesting the blue zenon bulbs shower the eye's with what's the most sensitive to the eye's, so even though it may be more effective agaisnt this common night time irritant unless your drivign head on along a highway full of zenon bulbs at other times this blue light is going to be the light your eye's are most sensitive too and if it gets filtered at night when the eye's don't really pick up too much of the other wavelengths in essence your left with reduced stimulus.

    Could it be more of the placebo effect rather than the medicine? I guess it's int he mind of the believer like mentioned here.
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  22. #47
    Eyes eastward... Uilleann's Avatar
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    Quote Originally Posted by Georg Mayer View Post
    I don't want to deviate off the subject, so, here's a link to Wikepedia:

    http://en.wikipedia.org/wiki/Galilean_moons

    chapter visibility. Only genuine optics, no acid ... ;-)

    Georg

    Better Best than Biggest
    In a way, it's a tangent, but still somewhat parallel to the original subject. :)

    The article does state: "The four moons were discovered sometime between 1609 and 1610 when Galileo made improvements to his telescope, which enabled him to observe celestial bodies more distinctly than had ever been possible before.[1] Galileo’s discovery showed the importance of the telescope as a tool for astronomers by proving that there were objects in space that cannot be seen by the naked eye."

    And goes on to say that: "All four Galilean moons are bright enough that they could, if they were farther away from Jupiter, be sighted from Earth without a telescope. They have apparent magnitudes between 4.6 and 5.6 when Jupiter is in opposition with the Sun,[38] and are about one unit of magnitude dimmer when Jupiter is in conjunction. The main difficulty in observing the moons from Earth is their proximity to Jupiter since they are obscured by its brightness.[39] The maximum angular separations of the moons are between 2 and 10 minutes of arc from Jupiter,[40] close to the limit of human visual acuity."

    Now bearing in mind, that under "perfect" dark sky conditions, like on a raft in the middle of the Pacific Ocean, the human eye can see an object with an apparent magnitude of no more than 6. (Objects being fainter as the number of magnitude goes up on a logarithmic scale) So you've got four objects THAT faint, so CLOSE to an object SO bright (Jupiter itself)...you ain't never gonna see them naked eye under anything other than highly unusual seeing conditions, with a "perfect" human eye. ;):cheers::cheers:

    Although...a goot hit or two of a particular mind-altering substance might help...LOL

    Cheers Georg!

    Bri~

  23. #48
    ATO Member HarryChiling's Avatar
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    Quote Originally Posted by Uilleann View Post
    Now bearing in mind, that under "perfect" dark sky conditions, like on a raft in the middle of the Pacific Ocean, the human eye can see an object with an apparent magnitude of no more than 6. (Objects being fainter as the number of magnitude goes up on a logarithmic scale) So you've got four objects THAT faint, so CLOSE to an object SO bright (Jupiter itself)...you ain't never gonna see them naked eye under anything other than highly unusual seeing conditions, with a "perfect" human eye. ;):cheers::cheers:
    So what your saying is there's a chance. :D:p
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  24. #49
    Master OptiBoarder OptiBoard Silver Supporter Barry Santini's Avatar
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    Quote Originally Posted by HarryChiling View Post
    So what your saying is there's a chance. :D
    you ain't never gonna see them naked eye under anything other than highly unusual seeing conditions, with a "perfect" human eye:p
    Yeah, his name is Stephan O'Meara!

    Barry

  25. #50
    Eyes eastward... Uilleann's Avatar
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    Quote Originally Posted by HarryChiling View Post
    So what your saying is there's a chance. :D:p
    Well...OK, I'll concede that there's a chance. But probably only if you got special magic eyeballs like what Tom Cruise got in his little plastic bag thing in Minority Report. And a great seedy scary surgeon and assistant to put them in for you of course! LOL :cheers::cheers::cheers:

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