I also agree with the above statments.
A bright gun light or spotlight, in my opinion, is not the best option when scanning for predator eyes. It is a common misconception that brighter is always better with lights.
Lights that use high-output LED’s with a smooth reflector housing and/or a magnifying glass lens to concentrate the focus of the beam can “burn” a predator’s eyes. These brighter lights may be acceptable for shooting but are not best for scanning.
The objective of a scanning light is to continuously scan the calling area, looking for the reflection of an approaching predator's eyes. The amount of light used should be as minimal as possible to avoid spooking the animal, yet enough to still see the reflection of its eyes at long distances.
Keeping this minimal light on the predator as it approaches also conditions the predator to the light. The predator gets used to the light as it approaches, and when it is within shooting range, the hunter then can transition to a brighter gun light for positive identification and the shot. This method does not overpower the predator’s photophobia (sensitivity to light), thus keeping the predator in range longer.
The Night Eyes Headlamp was designed specifically to minimize the chance of spooking predators while scanning. The orange peel reflector housing fragments and diffuses the red light beam, and a fully adjustable brightness control gives the hunter the ability to use as little or as much light as desired. This helps prevent burning the eyes, yet a hunter can still pick up those eyes at over 300 yards even if the center of the diffused beam is not directly shining on the predator. A high-quality gun-mounted light, such as The Night Eyes Light, will then enable positive identification of predators at distances of 200 yards or more, depending on conditions.
I am often asked if it is better to turn off the scanning light once the brighter gun light is shining on the predator. Basically, it comes down to preference. I prefer a hands-free headlamp for scanning, and leaving this headlamp on gives me one less thing to worry about. I attach a halo shield to the headlamp, which helps prevent unwanted peripheral light from shining in the scope.
The objective of a scanning light is to continuously scan the calling area, looking for the reflection of an approaching predator's eyes. A bright gun or shooting light in my opinion is not the best option and may spook approaching predators. I guess you could compare scanning with a gun light to hunting squirrels with a deer rifle. Sure, it will work, but there are better options. Save the bright gun light for positive target identification and the kill shot.
Regardless of what type of scanning light you use, remember to get them in close by not overpowering them with too much light. No lighting system, however well designed, will make you a better hunter. You still need to be mindful of good hunting tactics. But ask yourself this: "Am I shooting as many as I could be, or are they hanging up and shying away?"