This feature is only available on the following devices with firmware version 270 or higher:
C2-2105A, C2-2150A, C2-2155A,
C2-2250A, C2-2255A, C2-2355A
Frame lock on these units works by locking the output resolution frame rate to a selected input signal's frame rate.
1. 1280x720p 59.94Hz output could be frame-locked to a composite video NTSC (59.94Hz) source.
2. 1920x1080i 50Hz output could be frame-locked to a composite video PAL (50Hz) source.
Note that this can only work when the selected output resolution, and the selected input resolution are the same frame rate already.
The frame lock feature will ensure that they will stay aligned and do not drift apart once locked, but is unable to lock the output to an input of a different frame rate.
To perform a frame lock:
1. select your desired output resolution in 'Output res'
2. select your desired lock source in the 'Lock' menu
3. turn on 'Frame lock' in the 'Lock' menu
Note that it can take up to 2 minutes for the frame lock to stabilize on composite, YC and SDI outputs - DVI and RGB output generally lock up quicker than this ('Frame lock' will flash until a full lock is acheived).
'Frame lock' will flash until the output signal is stable to within 200ns of the lock source.
'H/V shift' can be used to align the output to the input more accurately, but this may cause instability until the lock is re-acquired ('Frame lock' will flash).
It is highly recommended to only use positive number for the V-shift, as the lock range is far wider for these than negative numbers. E.g. To acheive a -50 Vertical shift for a 1080i signal, use +562-50 = +512 (562 = number of lines per field, which is half the 1125 lines per frame).
Frame-lock is very useful for synchronizing a HD-SDI output (e.g. 1080i 59.94Hz) to a composite video source (e.g. NTSC), or for scaling one resolution to another while avoiding any potential frame-rate conversion artifacts.