Inputting and Outputting Media > Clip Input/Output Using a VTR > Working with Multi-Format Input and Output >

# Detection of Sync and Timing

In the following circumstances, Smoke checks whether or not your incoming sync matches the project timing you are working on:

- When you load a project on start-up.
- When you change projects in the Preferences menu.
- When you change preview timing in the Preferences menu.
- When you change your VTR to one with a different timing, or change the timing on your VTR.

If your video sync is correct, you can proceed as expected.

If it does not match, you are prompted to fix the sync and click Confirm. One of the following occurs:

- If you click Confirm without fixing the sync, the check is done again and you are not allowed to proceed.
- If you click outside of the Confirm button, you proceed in “free-run” mode, and using the workstation’s internal sync. You can work in this mode, but input and output can have unpredictable results. No more sync checks are done.
- If you fix the sync and click Confirm, the workstation is now genlocked. You can proceed as expected.

The incoming video sync is displayed in the preferences menu. See Timing Preferences.

When changing project timing, Smoke selects an appropriate VTR for you. The VTR devices available depend on the VTR keyword lines uncommented in the software initialisation configuration file. If multiple VTR matches are found in the list, Smoke selects the first match. If no match is found, VTR selection reverts to "No VTR selected" with the appropriate timing.

You can also manually select a VTR, as described in Selecting a VTR Device For Input and Selecting a VTR Device For Output.

NoteIf you are outputting a clip whose timing differs from the preview timing setting in the Preferences menu, the timing and VTR switch are done automatically by Smoke as soon as you select the clip to open the Output Clip menu.