Need help connect relay to surveillance camera
Just want to post the resolution in case anyone else ends up here with the same issue.

First, I have to admit I was being lazy because I didn't want to remove the camera from its mount to bring it to a place where I could do tests.  

I checked the voltage across camera pins 2 and 4.  I found 5VDC.  I connected camera pins 2 and 4 to the relay pins DC+ and DC-.  Resulted in green "power" LED illuminated.

Next, I connected camera pin 1 to relay pin "IN." To test, I went to the camera setup page and changed the digital output state from NO to NC.  No effect.  I then moved the relay jumper from low to high.  At that point, I was able to change relay by changing the digital output state on the camera.  

Calling it solved.  Now I just need to decide where to mount the relay and how to make the connections.

Thanks for all the assistance.  I love this site!