Autogating
A night vision tube feature that rapidly adjusts the tube's power when light gets bright, keeping the picture usable near headlights, yard lights or muzzle flash.
What it means
An autogated tube switches the power to its light-catching surface on and off very quickly, many times a second. When the scene gets bright, the tube shortens the “on” time, so less light gets amplified. The picture stays usable, and the tube is better protected from bright light.
Without autogating, a bright light makes a tube’s picture wash out or the tube shut down for a moment, and it can take time to recover.
What it changes in the field
Hunters run into bright light more than they expect: truck headlights on a county road, a farm’s yard light, a neighbor’s porch, the rising moon, and their own muzzle flash. With autogating you can keep watching the scene through those moments, and see the coyote after the shot.
It also helps at dusk and dawn, when the light changes fast.
What to look for
- Whether the tube is autogated. Sellers show it in many ways: a word in the description, letters in a model code, or a phrase about bright light cut-off.
- Autogating is common on current Gen 3 tubes and required on filmless tubes, which are more sensitive to bright light. It is less common on lower-grade tubes.
- Autogating is not a license to stare at bright lights. Protect any tube from direct, prolonged bright light.
- Manual gain is a separate control and works well alongside it.
How we use it on this site
We record autogating as yes, no or not published, from the maker’s specs. It is not scored.