Viewing a single comment thread. View all comments

DatsunL6 t1_j77n4m3 wrote

There is a blind spot in the center of our vision where the optic nerve comes through to spread over the retina.

Another way to "see" the effect you notice is with the stars. When you look directly at a star it will disappear because it's over the blind spot on the retina.

Or, maybe the LED you noticed is large enough to surround this blind spot and something else is going on.

1

Prestigious_Carpet29 t1_j78cegk wrote

Not quite true. The true blind-spot is a little off-axis from the centre of vision.

What you describe is the effect that dimmer stars may seem to "disappear" when you look straight at them because the centre of vision, the fovea (while having higher resolution and colour) is less light-sensitive.

3

DatsunL6 t1_j78wgh4 wrote

That's right. Dimmer stars disappear when directly looked at and it's not to do with the blind spot.

2

Ghitit t1_j7exhvd wrote

Any star I look at, bright or dim, disappears when I look at it because I have macular degeneration.

1