Q: I have had several commercial alarm accounts that are a problematic with recurring hold-up false alarms. The alarm circuits checkout fine and I really suspect the employees are accidentally pressing the momentary buttons, but don’t want to admit it. Please help.
A: Make the employees more responsible for their accidental hold-up activations. Install mechanical latching recessed hold-up buttons rather than simple momentary buttons. Give the manager a key and then there will be a clear physical indication as to which button was actually pressed. The recessed nature of the button will make it less prone to accidental activation.
Q: I have a customer that is complaining that not all the images in his CCTV picture are in focus. I have tried to adjust the focus on the camera but can only get part in focus. What am I doing wrong?
A: You are dealing with what is referred to as Depth of Field (DOF). To get both close and distant images in focus on a camera you need to either select a smaller lens format, adjust to a higher f-stop, and/or reposition the camera. If you are finding a camera in focus during the day, but out of focus at night then you will have to apply a technique call “back focusing.”
