Steevo25

Still new to the CCTV arena but learning fast. Just trying to understand the differences between MPEG4 compression format and MJPEG. Is one really noitceably better than the other. I understand that MPEG4 is a much smaller file size but have also read that MJPEG produces a better quality image. Looking at the DVRs on the market it always seems that MJPEG recorders have a smaller recording resolution when recording on a per camera basis. All the MPEG4 ones I have seen go to something like 700x576 ( or there abouts ) but the MJPEG specify recording resolutions such as 700x288 ( or there abouts ). Does this mean that the quality of a MJPEG DVR is offset by the smaller resolution and it produces smaller images even if the camera can support a higher resolution. And now, JPEG2000 seems to be on the scene.

Hi All, Hopefully you can sort out my confusion. Seeing various cameras advertised, I see some advertised as Day/Night cameras and others advertised as True Day/Night Cameras. What is the difference? All of them mention about a mechanical filter, some of them say dual filters. Is there a big difference or is it just terminology the various dealers are using? Thanks in advance.

Many thanks for your reply. I presently have 4 cameras on my system. Three of them work perfectly and both their day and night time image is perfect. The 4th camera I have a problem with. The day time image is excellent but the night time image is very snowy. The other problem I have with it ( the major one ) is that it is in my front porch ( which is an open front porch ) and currently it has IR. When someone approaches the porch, the IR is so strong and close to the person that the person is completely white and washed out. The porch also has a light in it that is PIR activated so this adds to the amount of light. Without lights the position is fairly dark, but there is a small amount of light from the street lights. Unfortunately, because of the space requirements and the position, I cannot use the same camera as the other 3 I have ( they are too big ). Also it is low down so would be better being a vandal resistant dome. My idea was to put a fairly good quality Day/Night camera without the IR LEDs in that position. It would give some sort of image at night with little lighting but would give a fairly good image when a person approaches and the porch light turns on. I have looked at a variety of cameras around the £250 mark ( about $500 I think ), but it seems every manufacturer details their specifications in a completely different way so comparing them is extremely difficult. The one there at present was supposed to be a good quality camera ( about $400 ) but so far I have not been impressed with it. I have been onto the suppliers several times and all the tweaks they have given me have failed to improve the picture quality. Also, to change any if the DIP Switches ( to turn off AGC etc ) you have to completely dismantle the camera which apparantly voids the warranty. This camera is being returned for a refund after a lot of arguing.

Mant thanks for your reply. Overall, I have been extremely impressed with the AVC760, and yes the HD is costing more than the DVR ( roughly double ). It is only used for home surveilance, and I was very apprehensive when I first bought it because it was near the bottom in terms of price. A friend of mine has a DVR that was well over double the price exclusive of disks and comparing his and mine, I really cannot see any difference. This has all the same features as his one ( except that on his one an external disk array can be added and it has a DVD writer ). In terms of picture quality and features there is absolutely no difference. I am trying to get 15 days stored on the disk as if I go on holiday, it is never for more than 2 weeks. As it stands, I get about 11 days in best quality and 25IPS Frame. It currently has a 500GB in it. If I put a 750GB then that gives me about 15 days using the best quality I can get with the unit. Thats perfect for what I require. I did email AVTech asking them if there was any way a 2nd HD could be added or if a 750GB would work. The said that it would not be possible to add a 2nd drive but confirmed that a 750GB drive would work in the unit.

Hi All, I am a complete newbie when it comes to CCTV, but I have installed one in my home and it all seems to be working very well. It definitely meets the criteria that I had wanted. There is, however, one thing that I want to do and that is increase the hard drive space of my DVR. I have been told by the manufacturer that the DVR ( AVTECH AVC760 ) can take a 750GB drive. They didn't tell me what specification the drive must be though and it takes a while to get any reply by email ( they are in Taiwain and I am in the UK ). Does any one know what the likely spec of the hard drive would be ( I know its IDE, but what RPM etc etc ). Many Thanks. Steve.