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  • #16
    Sniper-66:
    You make some excellent points, especially regarding NVGs. However, my comments about green vs. red were from the point of view of the shooter using an illuminated reticle for a long period of time at night, just like we use them during the day. In that case, I think the green illum will have more impact on the rhodopsin than would a red illum. Either that, or 25 years of using illuminated reticles when looking at faint targets (stars and nebulae) has totally mislead me....
    Cheers,
    --Hawk
    There are few problems a well-placed 308 cannot cure. --- Hawk

    Gentlemen! You can't fight in here! This is the War Room! --- President Merkin Muffley in Dr. Strangelove

    Rocket Science is much more fun when you actually have rockets! --- USN Recruiting Commercial

    A little revolution now and then is a good thing --- Thomas Jefferson

    Only the dead have seen an end to war --- Plato

    "In Ireland, in Lebanon, in Palestine & Berkeley, Patty Hurst, heard the burst, of Roland's Thompson gun & bought it!!!" --- The Late Warren Zevon, Roland The Headless Thompson Gunner

    In the 1500's, the Roman Catholic Church sold indulgences to forgive sin. In the 21st century, we call these carbon offsets. ---Hawk

    �Fight like a man, so you will not have to die like a dog� --- Calico Jack Rackham's Mistress

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    • #17
      The green will only have a more negative impact on the rods if the intensity of the light entering the eye is of a greater value than the intensity of the red light. Rods only see in shades of grey, so if you have the reticle brightness of a green reticle at a low level and a red reticle on high, the red will wash the rhodopsin out faster than the green. However, my point was that when shooting through a scope, you are using the fovea centralis which is almost completely cones, hence day vision. Unless your scope has magnificent light gathering capability, the image will be quite dark and the peripherial vision that the rods provide will be of little use. That is the problem with using color in a grey world, the brain makes the color take over, thus the fovea centralis covers the reticle and in very short order, you will not see anything in a 5 to 7 degree cone except a seemingly floating colored reticle on a black spot. Now, you mention looking at stars and nebulas, those provide adequate light to stimulate the cones, therefore, the cones work well seeing them, much like laying the crosshairs of a scope on a distant light is easy to do. If you take a scoped rifle with a lighted reticle and look over a grassy field that is celestially lighted sufficiently, you may be able to use the lighted reticle. If you are in a wooded environment where there is overhead cover that blocks all light and you try to engage a target with a lighted reticle and well dark adapted eyes, you won't have any luck. Now, binoculars on the other hand at night may be useful as you can move them, scan and use the monocular clues of schotopic vision to aquire targets and possibly transition to a scope.
      I guess my bottom line is that when using a scope at night, if you don't have some photopic capability, you are going to be just taking shots in the dark, no pun intended.
      Good discussion though, not many people have a good grasp of how the eye works. I teach this stuff militarily and now am contracting out to law enforcement agencies, giving basic ground classes to both SWAT and flight detachments. You ought to see the quizzical looks when I talk this stuff to someone who has never heard it before!

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      • #18
        all that are very interesting and im with your for the red
        more simply if one <strike>day</strike> night you use night vision goggles youll see all in green so i think its more difficult to find green reticle in green vision than red who is opposed in the cromatic circle
        " IF AT FIRST YOU DON'T SUCCEED, USE DUCT TAPE !" said Uncle Bowe

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        • #19
          I think it has been 4 decades since I have heard the word Angstrom.[/b]
          Apparently your not a Tequilla drinker. "Angstrom" is a very common sound around shot # 7 Sometimes pronounced "Awgstrom"or "upupawgstom, dang, gimme another"
          Just trying to keep the world safe from Coyotes, Bobcats and dope fiends.

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          • #20
            About altitude.

            As I recall from night flying, if you don't smoke and are in good shape, ie no COPD, I remember starting to lose some of the lights on the ground above 5000 ft MSL. Smokers start losing it at 2000 or 3000 ft MSL. I am talking about lights on the ground. If we talk about unlit targets, the altitude would bother that kind of vision worse and at lower altitudes.

            A pilot doesn't move too much. Walking on the ground would seriously deplete oxygen and worsen vision.

            The problem with smoking is the carbon monoxide that accumulates and prevents getting good oxygen concentrations. That would take days to wash out. An oxygen bottle would help by increasing SpO2 right now, but if the oxygen were stopped, the help would disappear in only a few minutes.

            To altitude acclimate, it takes about a week to build up more hemoglobin. The younger and healthier the better the response. A good diet would be essential.

            dihedral

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            • #21
              Hawk, you really prove that shooting is more than just yanking on a trigger. There are so many factors that contribute to where your bullet will hit. And being able to see your target is obviously the most important. Great info.

              Adam
              Slow is smooth, smooth is fast.

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              • #22
                There's heaps of science in there that I had no idea about - that's for sure. I would've said that if you were going to use your scope in conjunction with some sort of night scope (UNS or DIOP) that the picture is going to be in green and black anyway so you might as well go for red which will stand out better.

                If you're using the scope for work rather than just civie hunting though I'd recommend you turn the illumination reticle on and look at it from the other side. In some scopes you can see that illuminated reticle from the muzzle end which isn't too flash tactically.

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                • #23
                  We had a medic with us that was red/ green color blind. He had a lot of trouble qualifying when we went to the CCO on our M4's. Red dot against a green target just didn't work for him.
                  War is an ugly thing, but not the ugliest of things; the decayed and degraded state of moral and patriotic feelings, which thinks that nothing is worth war, is much worse. A man who has nothing for which he is willing to fight; nothing he cares about more than his own personal safety is a miserable creature who has no chance of being free unless made and kept so by the exertions of better men than himself.- John Stewart Mill

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