baywatch Posted October 15, 2005 Share Posted October 15, 2005 We didn't network it as it was a domestic install. We used 2 x C70 cameras (from RF) with built in I.Rs to look over yard on smallholding (its not a high security situation just neighbour dispute). Day time images looked good, haven't see the after dark images yet. We also installed audio. We were impressed by the number of features & motion detection settings. We managed to get the motion to ignore the many chickens but trigger when one of us entered the yard. The search features also looked very user friendly but we left before it had recorded enough to try all the features. I will be visiting the customer again next week, let you know how its going. Link to comment Share on other sites More sharing options...
jizzer Posted October 15, 2005 Author Share Posted October 15, 2005 We didn't network it as it was a domestic install.We used 2 x C70 cameras (from RF) with built in I.Rs to look over yard on smallholding (its not a high security situation just neighbour dispute). Day time images looked good, haven't see the after dark images yet. We also installed audio. We were impressed by the number of features & motion detection settings. We managed to get the motion to ignore the many chickens but trigger when one of us entered the yard. The search features also looked very user friendly but we left before it had recorded enough to try all the features. I will be visiting the customer again next week, let you know how its going. Yes great I would be interested to see how this performed ..Thanks Baywatch Link to comment Share on other sites More sharing options...
Guest Lee Tracey Posted October 21, 2005 Share Posted October 21, 2005 I hate to be picky, but what I think RF concepts meant to say is .... there are two fields in a frame.Either that or the electronics industry has been getting it wrong for perhaps the last fifty years Congrats! You spotted the mistook as well. Actually they are all wrong. A TV picture is made up of 25 odd fields and 25 even fields and together they make one frame. Those of you with grey beards will remember the early analogue video recorders jumping from picture to picture when in STILL. This was due to the electronics jumping from the odd field to the even field and back again. Then rocket science entered the scene and they dropped the even field or the odd field and made a still on just one field - no more jittery images. But now we are digital and only the very very top DVR's actually provide the odd and the even fields for the very act of conversion from analogue to digital destroys that concept. In digital we have only IMAGES PER SECOND. So we talk about the DVR being able to record 25 images per second or as one Midlands City Council is about to do by walking ibackwards into the dark ages, fit a system at 2 images per second. This means that the resolution of the system is the maximum image rate it can provide. Very very few can provide 25 images per second on all 16 cameras at the same time - that would mean 400 IPS Global. Many claim to do so but not when they visit my lab and I switch their machine on and show them the truth. But even if a DVR can do 25 images per second it is only still 25 images per second. That is the same as the analogue TV system dropping all the odd lines or all the even lines - remember 25 fields and two fields make a frame. So the old TV was actually 50 images per second but in old jargon 50 fields per second or 25 frames per second. Now with digital we have images per second so fields and frames are no longer in the picture. There is one DVR company Wavelet Technology Ltd that can actually deliver 50 images per second so their machine ( win the lottery to buy one ) is on an equal footing with the old full frame analogue but no longer odd lines or even lines just images. To recap - the old analogue was 25 frames per second ( but each frame made up of one even line and one odd line ). The new digital ( the quality systems ) also provide 25 images per second. Is the quality the same? I am afraid that has nothing to do with it. A DVR can provide 25 totally **** images per second or 25 good images per second - too many other factors involved. QCIF is 176 x 144 - CIF is 352 x 288 - 2CIF is 704 X 288 - DCIF is 538 x 384 - 4CIF is 704 x 576 All the above relate to PAL. Some manufacturers make to slightly different figures, such as 720 instead of 704. The last number, like 576 in 4CIF is the number of lines and the first figure like the 704 in 4CIF is the number of pixels per line. Your cheap £300 DVR will probably only work in CIF or maybe only QCIF. Obviously the image quality of a DVR making 25 images per second in QCIF is going to deliver a vastly lower quality image than a DVR making 25 images per second in 4CIF. You gets what you paid for. If your DVR can only deliver, recovered image from the hard drive, 200 TV lines then there is no point nor reason in buying a camera that can do more, Lee Tracey Link to comment Share on other sites More sharing options...
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