the toss

Jamie Hyneman from Mythbusters demonstrated that a PIR can be beaten when the intruder covers his body with a cotton sheet. . As tomcctv has stated you will not beat a modern PIR with a bed sheet ( or a wetsuit or flooding the room with IR ) Any PIR worth its salt will utilise adaptive ambient analytics , anti masking & a host of other "smarts". Besides detecting a moving IR source a PIR will also detect a negative moving IR source ( ie someone who has successfully deleted their IR image. Optex PIRs - one of the best value for money PIRs available.

Fiona , where in Australia are you from ?

Ghosting is usually the result of impedance mismatch. What type of cable are you using ?

I'm guessing that your climate would be pretty similar to here in Australia & I've found no need for heater or fan in a camera housing for the 18 yrs I've been doing this. 2) yes the glass is usually glued in

It is determined by the flange to sensor spacing. A "C" type lens can be used on a "CS" camera by using a spacer ring to correct the focal length. A "CS" type lens cannot be used on a "C" type camera because the focal length will need to be decreased which cannot be achieved short of savage butchery with a file / angle grinder

The problem here is twofold. First by not using baluns there is an impedance mismatch ( 75^/100^ ) This results in an unbalanced transmission path & causes loss of the noise immunity that is characteristic of twisted pair. Now if the ONLY problem was the impedance mismatch then the result would more than likely be a phasing problem (ghosting). The interference displayed in the picture is typical of an external electrical interference getting onto the transmission path because of the reduced noise immunity created by the impedance mismatch ( lack of baluns ). The other clue is that the interference is only there during the day

You miss the point. It doesn't matter where you crap. There are some things you don't want or need an audience for. It doesn't mean that it is illegal or you have anything to hide. You may be comfortable being scrutinised but that doesn't mean you set the standards that others should be comfortable with.

Do the cameras have OSD & setup ? If so try adjusting the colour saturation

Sure why not, what do you have to hide? So when you have a crap do you close the door ? I bet you do & it makes me wonder what you have to hide ?

Many DVRs are sold without the HDD installed , have you checked ?

Just came across this forum & the discussion seems to be of such a high qualiy I just had to sign up. I am a proffessional electronic security installer & business owner with a background in telecommunications (mainly microwave radio). I look forward to picking up tips & sharing my own knowledge