About tri-level sync
The K2 Summit system automatically detects, switches, and syncs to the reference. When you configure the reference standard for either NTSC (59.97Hz) or PAL (50Hz) in K2 AppCenter Configuration Manager, a restart is required to put the change into effect and the system starts with a SD reference format by default. It then attempts to detect a reference in a format and frame rate that is compatible with the current reference standard setting. When the K2 Summit system detects a reference in a supported format, it automatically switches to that format. This allows the system to switch between SD and HD tri-level formats with frame rates that are compatible with the reference standard setting. When the K2 Summit system locks to a new reference format, it saves the format and frame rate information, and upon restart it returns to the saved format and frame rate.
Do not use a progressive reference with an interlace output. For example, do not use 720p tri-level sync for interlace output formats (such as SD and 1080i). Output timing can be off by a field with this type of incompatibility.
In these cases the K2 Summit system internal genlock flywheel provides a stable reference for the last reference set. The system reports this status in K2 AppCenter Configuration Manager Reference Standard by a black "Reference present" indicator.