Need help with 4ea HTC-207 (CCD Digital Color Camera)

[any ANONYMOUS forum user]

I bought 4ea HTC-207 cameras which are supposedly Sony. However I have also learned that Sony doesn't list such a model number either. The cameras did not come with any instructions as to their setup. They all have Auto Iris CCTVLENS 3.5mm-8mm, F1.4. The dip switch setting I need to know what position to set in has three labels, DC, Lens, and Video. Which position should I use for the auto Iris adjustment? (It seems or feels like the switch has a detent either for Video or the DC position.) I have a wired system to a 4 Channel DVR. I also am installing these cameras in housings which are heated and cooled due to the area I live in. I forgot to mention that the Lenses have thumb screws that can be locked or unlocked which I think I understand how they work but I am not cetain either whether or not they should be left tightened down or left loose? Any help would be appreciated. JK