how do we focus in the dim light?
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Night vision\n\n Two American soldiers pictured during the 2003 Iraq War seen through an Image IntensifierNight vision is the ability to see, whether through biological or technological means, in a dark environment. Most instances, whether biological or technological, use a combination of two approaches: enhanced spectral range, and enhanced intensity range.\n\nContents [hide]\n1 Enhanced spectral range \n2 Enhanced intensity range \n3 Biological night vision \n4 Night glasses \n5 Thermal vision \n6 Image intensifier \n7 Night vision goggles \n8 See also \n9 Patents \n10 External links \n \n\n\n[edit] Enhanced spectral range\nEnhanced spectral range techniques make the viewer sensitive to types of light that would be invisible to a human observer. Human vision is confined to a small portion of the electromagnetic spectrum called visible light. Enhanced spectral range allows the viewer to take advantage of non-visible sources of electromagnetic radiation (such as near-infrared or UV radiation).\n\n\n[edit] Enhanced intensity range\nEnhanced intensity range is simply the ability to see with very small quantities of light. Although the human visual system can, in theory, detect single photons under ideal conditions, the neurological noise filters limit sensitivity to a few tens of photons, even in ideal conditions [1]. Some animals have evolved better night vision through the use of a larger optical aperture, improved retina composition that can detect weaker light over a larger spectral range, more photoefficient optics in the eye, and improved neurological filtering which is more tolerant of noise. Enhanced intensity range is achieved via technological means through the use of an image intensifier, gain multiplication CCD, or other very low-noise and high-sensitivity array of photodetectors.\n\n\n[edit] Biological night vision\nIn biological night vision, molecules of rhodopsin in the rods of the eye undergo a change in shape as light is absorbed by them. The peak rhodopsin build-up time for optimal night vision in humans is 30 minutes. Rhodopsin in the human rods is insensitive to the longer red wavelengths of light, so many people use red light to preserve night vision as it will not deplete the eye's rhodopsin stores in the rods and instead is viewed by the cones.\n\nSome animals, such as cats, dogs, and deer, have a structure called the tapetum in the back of the eye that reflects light for even better night vision than humans, in which only 10% of the light that enters the eye falls on photosensitive parts of the retina. Their night vision likely falls between a Generation 1 and Generation 2 image intensifier.\n\n\n[edit] Night glasses\nNight glasses are telescopes or binoculars with a large diameter objective. Large lenses can gather and concentrate light, thus intensifying light with purely optical means and enabling the user to see better in the dark than with naked eye alone. Often night glasses also have a fairly large exit pupil of 7 mm or more to let all gathered light into the user's eye. However, many people can't take advantage of this because of the limited dilation of the human pupil. To overcome this, soldiers were sometimes issued atropine eyedrops to dilate pupils. Before the introduction of image intensifiers, night glasses were the only method of night vision, and thus were widely utilised, especially at sea. Second World War era night glasses usually had a lens diameter of 56 mm or more with magnification of seven or eight. Major drawbacks of night glasses are their large size and weight.\n\n\n[edit] Thermal vision\nFar infrared, or thermal, sensing is generally not considered night vision because it is constructed with mechanisms substantially different from the methods used to sense visible light. It is possible to construct an imaging device with microwave energy, sound, or any other signal that is reflected or radiated by objects and can be focused and sensed, but these are also not genera
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use a blacK light and see what happens
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Look up your instructions.  You will most likely find a button on the monitor with what looks like a 'sun' on it which if you play around with it, will dim or brighten the screen.
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reduce your light on the screen if no change see an optician they will advise you
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global dimming is a very worrisome factor. By the turn of the next century we will have more dimwits than at any other time in the history of mankind. Already this phenomenon has become a global concern. So many people's brains are dimming.
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u see darkness because light isn't present. Not whether is it possible to look at nothing.
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Wear magnifying lenses.
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I think maybe the separation is smaller than the resolving power of my eyes rather than the angular separation of my eyes. So I can't resolve the two sources and just see one bright star. \n\nBest of luck - Mike
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Zero....Illumination is tracked by the speed of light but the lack of illumination means that nothing is moving.
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Always make sure that the light is behind the camera, else the auto-exposure will close down, giving you a rubbish result. To cut the jerkiness you may be able to increase the frame rate on setup. Also go to 'Properties' and shift the 'Gamma' this may help.
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Have you tried adjusting the brightness? There are buttons on your monitor. There should be one for exit, one for selection and two for scrolling. click the selection button, then use the scroll buttons to reach the thing that looks like a sun.. click the selection button again and then click the scroll button to move it brighter. then click the exit button. you may also have a dying monitor. is it a crt (fat bulky one) or an lcd (flat panel) one
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Repost your question so it makes sense! Either you found your monitor brightness control or you didnt! You may also be able to adjust gamma and brightness in your desktop properties. Give details on what monitor you have and what PC you have!
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Not sure how to do that one i would ask the actual person or person's maybe they will inform you how,as they are the one's that are blind ya'know?\nthat is a good Q? though :)
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You are not very bright are you?
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I have the same problem, I just found out I need glasses for it, but also for distance and stigmatism.  Nice combo, basically I need bifocals at the age of 25. :(  But the doc did say the computer is bad for the eyes, so every 20 minutes, you should look 20 feet away and look at that place for 20 seconds. 20/20/20.  It is supposed to help your eyes refresh.  Sleeping a full night helps too, don't forget to blink, use drops if needed.  The problem with computer screens is that each tiny pixel in the screen is moving on its own, almost flickering.  We can't see it because the flicker and pixels are so so small, but the eye needs to use more energy to focus on that screen, thus damaging your eye sight.  Get glasses, computer glasses, they are supposed to help, I am waiting to buy mine because I don't have eye insurance in 2006, but will sign up for it in 2007.
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focus on a point in front of you.\n\nbetter yet, focus on TWO POINTS
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Stay focuse!\n\nSlowly and easy does it!