Well, human light perception shifts drastically based on ambient conditions; you can see how fast the camera drops off as you reduce the light levels, whereas the human eye compensates fast (by dilating).
Most humans come to full night-vision in about 15 minutes, although some are faster and some are slower. Most of this happens in the first 30 seconds or so -- note how a bedroom is dark when you first get in bed, but if you wake up later (for whatever reason) it is normally pretty easy to navigate, albeit in black and white.
In normal light, a low-power source, especially at the blue-end of the spectrum will be outweighed by red and yellow sources such as the sun.
In very low light conditions, however, it is the only light source, so it seems brighter.
Blue light has a lot of energy for it's intensity, so at any given power it seems brighter, this is why night-ready environments (such as fire-control or C&C on a battleship) use red lighting in night ops to reduce the time it would take the eyes to switch back to full night vision. For the same reason, emergency vehicle use a blue light (in Europe anyway) because it is more piercingly bright.
hi there i like to tell yhat i'm using a keychain torch light .working with the same led technology it's to bright and even it could damage your eyes if you look at it. we are not talking in optometry it's just life fact.
Linear Mode
