Optionally other fields of view may be provided. Their selection should be made with a non-locking switch, which returns to the required field of view when released.
5.2.5 Pan range of the field of view
The axis of the field of view should be capable of being moved at least 20｡?orizontally to either side.
5.2.6 Pan speed of the field of view
By activation of a single control element, the axis of the field of view should be capable of being returned automatically to the ahead position at a minimum angular speed of 30°/s.
5.2.6bis Vertical trim of the field of view
The vertical axis of the field of view should be capable of being adjusted no more than 10｡?o compensate for the trim of the vessel.
5.2.7 Heading indication
When inside the field of view, the heading of the craft should be indicated by a marker on the display with a maximum error not greater than +/- 1 degree.
When outside the field of view a visual indication of relative bearing with a maximum error of +/- 1 degree.
5.2.8 Roll or pitch
The performance requirements in this standard should be achieved under the normal roll and pitch conditions experienced in high speed craft.
5.2.9 Clear view
Arrangement should be provided to ensure efficient cleaning of the sensor head/lens from the operating position.
5.2.10 Interference
The surroundings of objects commonly encountered at sea and in ports should not be displayed less clearly on the monitor of the night vision equipment because of dazzle effects, reflection, blooming, or any other effects.
5.3 MALFUNCTIONS, WARNINGS, ALARMS, AND INDICATIONS
Night vision equipment should have the following displays
- state of operation;
- visual alarm in the event of failure of the night vision equipment;
