1. With Dahua camera working on Dahua DVR, right click live view select PTZ control.

2. Click the “+” iris, which should bring up the OSD (on screen display) menu.

3. Use the directional buttons to navigate to Advanced and click iris "+".

4. Navigate to "Video Type"  and use the directional buttons to select a different video mode.

(If camera is going onto a Viper use TVI).

5. Click iris "+" to select the new video mode and again to confirm it.