For all my HikVision Cams I have the model number from the web user interface, e.g. DS-2CD2132-I. However, how do I determine if this is a 2.8mm, 4mm or 6mm cam? The web interface doesn't seem to have that information and neither does SADP. I want to replace them with better models and in some cases also higher zoom but need some kind of reference point. I would prefer not having to take down the cam to look at the label.