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Motion sense versus record 24x7

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I have a CPCam 576W 9ch DVR with a 250GB hard drive. Right now I have it recording 24x7 and that gives me approx 3 days of video. The system is limited to 25fps, so with 9 channles thats about 3fps per channel.

 

If I switch to motion sense video then I can get a lot more than 3 days, but I'm concerned about missing something that doesn't trigger the motion.

 

How many days retention is 'enough' for a residential system? Would it be better to put in a bigger hard drive, or go to motion sensing? With motion sensing do you start off with it beign higly sensitive and turn it down over time? I use the motion sensing feature as an activity log, but still record 24x7.

 

I'm also hoping that I'll get a better frame rate if only the motion cameras are recording.

 

 

EDIT: Just switched all the cameras to event-based recording and tested it. Walked around and into shot of all the cameras one by one. When the motion detect is tripped, the camera ramps up to max FPS and the rest drop to 1fp. When two cameras are tripped, they share the max FPS. This is a great setup - much longer record time, all the cameras still record at a lower framerate so you still have the context provided by the rest of the cameras, and a good 15fps on the camera that has the action.

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I'm not a big fan of motion based recording. It can lead to missed video, and I think it makes an incomplete record for evidence purposes, in case the video needs to be introduced at trial.

 

I'll give you an example that happened to me. Once a neighbor's car was hit while parked in front of my building.

 

A week prior to this incident I was playing around with motion recording on the DVR and left it enabled to see how it would do. I left it set for "Outdoors, medium sensitivity" with no masking.

 

Well, I told the guy not to worry, we should be able to see the vehicle that hit his parked car, as there was a hi-res Sanyo D/N box cam positioned on the building close to the car. I would burn a CD and he could take it to the police. We suspected it was a truck that caused the damage, therefore we had a good chance of seeing the name on the side.

The car was pushed up on the curb from the impact, making the "before" and "after" easy to located in playback.

 

Well you can imagine my embarrassment when during playback, with my neighbor watching, the motion detection had stopped the recording at that critical moment. There was video before and after the accident, but not during, and we could not see the truck.

 

I told them I was sorry, but we could not find the video they needed.

 

Since then, no more motion detection for me. When I setup for a client I leave motion off, if they decide to turn it on they do so at their own risk.

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Its really up to you. 90% of my clients use the motion detection feature unless its a retail environment and then they run continous during business hours and motion in the off hours.

 

If 3 days is good enough for you, then leave it on continous. The max fps on motion feature sounds like its benefits for you so you'll just have to play with it. You should also be able to mess with the lenght of time it records when it detects motion, I normally don't set this less than 10 seconds.

 

Whatever you do, always test it out. If you set it for motion, make sure you test it out, even more than just a simple walk around of the house. Leave it set for an hour and really play with it!

 

Let us know what you decide to do...

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I use 100% motion detection, with no issues. It really depends on the DVR you are using, but also, just as important, you must thoroughly test each camera with motion, in each lighting condition, to get the best sensitivity setting for each camera.

 

Its best to raise the sensitivity to just below max on priority cameras (eg. 9 on Geo), even with that, you save alot of recording space.

 

On a GE Storesafe for one example, 40Gb with 4 cameras, we get just over 1 month recording at a mon-fri business center. Have had many incidents and never missed one yet.

 

At the night club no issues also.

Course if you got the cash for 3TB+ of Hard disk space, then worth doing Continous Record, though most apps dont call for that nor can afford it.

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I did have an event happen a couple years back (snow plow trashed my mailbox) that would not have been captured with motion detection only. The mailbox was 150' from the camera and was only about 4 or 5 pixels high, plus I mask off the road otherwise every passing car would trip it.

 

3fps is pretty bad. It's nice to see some smooth video being recorded.

 

I'll start with the recording in super-sensitive mode and will back off the sensitivity over time as I see the kind of events that are getting captured.

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150' away, you wont be able to identify the object or person anyway, and wont be usable in court.

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150' away, you wont be able to identify the object or person anyway, and wont be usable in court.

 

Understood. In this case, though, it was enough to convince the county engineer that his plow took down the mailbox. No courts involved, and the mailbox was only worth $5. You could see the mailbox go from vertical to horizontal as the plow passed.

 

 

Another problem re: courts was the video did not download in real time. This was a cheap ebay dvr card and the software was bad.

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i watched a guy stab another guy to death (recorded video) at approx 75' away, and the judge through it out ..

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i watched a guy stab another guy to death (recorded video) at approx 75' away, and the judge through it out ..

 

At that distance (assuming it's not a zoom lens) there's not going to be enough detail to positively identify a person. He's just going to be an unidentified blob on the screen unless he approaches the camera in the same shot, there is some other positive identification such as multiple witnesses who say it was him, *or he admits that it was him*.

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Some DVR's have a feature that you can set how many seconds before and how many after the end of motion to record. Default on mine is 5 seconds on both. I changed it to 5 pre and 30 seconds post. I'm pretty much covered and save a whole lot of disk space.

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Some DVR's have a feature that you can set how many seconds before and how many after the end of motion to record. Default on mine is 5 seconds on both. I changed it to 5 pre and 30 seconds post. I'm pretty much covered and save a whole lot of disk space.

 

I can't set pre-motion, but post-motion is 20 seconds.

 

Something else I found is that my little CCTV TV doesn't show the full width/height of the image. I can see the full image when I turn on the TV capture card software on the computer next to it (i use the capture card to make DVDs of the action). This helped reduce false alarms on the motion because there were some areas I should have excluded from motion sensing that weren't visible on the TV.

 

It also has a built-in feature that will send an image via FTP and means I can set up an FTP server on my computer and create a thumbnail gallery of the motion events during the day. Once a day I can glance over a page full of images and be able to see which images contain useful footage. Then I can use the motion event from the log in the DVR and replay the event from that time - If someone comes by casing the house then I'll see them.

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Its an AvTech DVR. .. one of the cheapest on the market, they created the name CPCam to push marketing to North America, trying to get away from their identity as a manufacturer of budget DVRs, the same exact DVRs which have been sold in stores like Sams Club and KMart, but basically they are the same, with all the same features, or lack thereof. One thing that I never liked was the low quality of their Remote Client software, and their Java Browser based. I had hoped they would at least improve that for the CPCam name, but they didnt.

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I've found MD to be pretty poor, unless the motion objects

are quite sizeable in comparision to the screen size.

 

As a better alternative to 24x7 recording, I installed IR motion

detection to initiate recording as well.

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I've found PC based to be stable & accurate.........standalones can have issues.

 

Lots to consider and think out. motion on 16 camera's (FPS & RES maxed out) in a mall during peak is going to drive a CPU to max. real quick, possibly causing some missed recordings. 16 camera's installed at a home residence...well, your luck if you have 2 camera's recording at once...........unless it rains.

 

I stick with 24/7 on stand alones and motion with PC based. Have been happy with both. Latest Codec's have made 24/7 stretch the hard drives.

 

Bottom line is you need to consider the "box" you are buying, the camera's you are attaching to it, and the expected video results. Match the "box" to your requirement and then double the processor if you can!

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I guess this depends on the dvr model you have and its specification. With mine, I can set the recording rate individually for manual record mode and motion detect mode. I set both manual record mode and motion detect mode. With manual record mode...I set to the lowest frame rate but with motion detect I set to the maximum frame rate. So when I view the video including the pre-alarm recording...the pre-alarm recording shows the low frame-rate but then when actual event comes, the the frame rate increases to the maximux set.

 

But I switched off manual record mode since it is such a hassle to sip through all the uninteresting recording whereas motion detect shows you exactly what you need. It also has the pre-alarm recording meaning it is always recording into memory all the time and only records to disk when the event happens including about 1 minute of video before the motion detect is triggered. The post detection after all motion has stopped is maximu set to 40 secs. I have the avtech761.

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Motion detection with lots of cams may not always drive a cpu to its limits, it depends on the dvr or dvr card. With a geo 1480 for example the chips they use have in-built motion detection, which is why I think geo has now got two seperate motion detection bits (ie standard and advanced). If I recall (its been a while since I read the chip specs) the onboard chip is capable of fully handling the standard geo motion detection. It also explains why the two are seperate, and not one and the same. One they added because it was easy to do, the other they added due to the first not being up to scratch....

 

As for motion detection, I use it, but I also have a permanently recording backup dvr, as motion detection always seems to be fine, apart from now and again when its not... Hard to figure out why, or to reproduce, but its never perfect for me.

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Motion detection with lots of cams may not always drive a cpu to its limits, it depends on the dvr or dvr card. With a geo 1480 for example the chips they use have in-built motion detection, which is why I think geo has now got two seperate motion detection bits (ie standard and advanced). If I recall (its been a while since I read the chip specs) the onboard chip is capable of fully handling the standard geo motion detection. It also explains why the two are seperate, and not one and the same. One they added because it was easy to do, the other they added due to the first not being up to scratch....

 

As for motion detection, I use it, but I also have a permanently recording backup dvr, as motion detection always seems to be fine, apart from now and again when its not... Hard to figure out why, or to reproduce, but its never perfect for me.

 

I take a similar approach.

 

The UK law on evidence states that evidence must be complete and not an extract, so motion only recording is open to a challenge.

Motion only recordings are not inadmissible in UK courts but advice is to record continuously.

Advice to police when submitting cctv evidence from public areas is to include recordings 10 minutes before and after an event.

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