Hoping someone can help me get a better understanding of the sensitivity and threshold settings within the motion detection event setup.
I've mounted 4 cameras on the outside of my house, and set events to record and send email upon motion detection. I've been playing with the sensitivity, threshold, and anti-dither settings, but cannot seem to get the settings such that I am not getting 300-400 emails a day when it snows. I'd like the system to be set such that I'm alerted when someone physically walks in the detection range, but not so sensitive that a windblown branch or snowflake sets it off.
I've currently got motion detect zones defined for all 4 cameras, with a sensitivity setting of 30, a threshold setting of 25, and an anti-dither setting of 300 for each. Could someone offer suggestion on what I should have these various parameters set to in order to lessen the number of triggers but still pick up on large activity?
final question - regarding snapshots & email of the picture - I see that there is a minimum 10 second delay in recording an event triggered by motion detection. does the snapshot taken at motion detection also on a 10 second delay? I'm wanting to get a snapshot of what actually triggered the motion detect system, not the field of view 10 seconds later. am I misinterpreting how this is happening, or is there a setting tweak I should make to ensure I'm getting sent a snapshot of what triggered the system at the time of trigger?
thank you!
Motion Detection Sensitivity / snapshot of MD trigger
Re: Motion Detection Sensitivity / snapshot of MD trigger
I'm about in the same place as you. I have my cameras outside and just want to be alerted to a person walking by the camera.
Here's are the problems and my best solutions so far:
1. If the camera is outside, and covering a large area, that is a lot of potential motion to occur. Like, snow or leaves. I'm not really sure if you can set the sensitivity and threshold high enough to not be triggered by a screen full of snow, and still pick up actual human movement, but maybe play around with the settings and test it out.
2. The best solution I have come up with is I put my cameras close to any entries I want to cover like the back door, and I only put the motion detection zone right around the door and keep the sensitivity and threshold high enough that I'm not getting a bunch of false alarms, but make sure it still detects when I walk by the door. This way, if an intruder walks up to the door it will alert me, but I'm not covering a large area that has the potential for a lot of false alarms.
3. I have my anti-dither set as low as possible. Not sure what it does but I think you get better snapshot of the actual movement the lower it is. I actually have my snapshot set to send 5 snapshots but I can only get it to send me one. Not sure how to get that to work right. In the email settings, it has a delay as well. For this one, if you set to 30 seconds, you will get one email for a motion, but won't get another alert for more motion until 30 seconds has passed from the first alert.
The best advise I can give is keep increasing your sensitivity and threshold levels and testing that out and/or select smaller areas of motion detection so that your now covering so much area. I haven't really tried just setting both levels high and covering the whole screen but maybe that would allow for only major movement like whole person to set it off instead of small objects like leaves.
The whole system is confusing and the manual doesn't have good definitions of what all the stuff does but if you just keep trying different settings you can somewhat get where you need.
Here's are the problems and my best solutions so far:
1. If the camera is outside, and covering a large area, that is a lot of potential motion to occur. Like, snow or leaves. I'm not really sure if you can set the sensitivity and threshold high enough to not be triggered by a screen full of snow, and still pick up actual human movement, but maybe play around with the settings and test it out.
2. The best solution I have come up with is I put my cameras close to any entries I want to cover like the back door, and I only put the motion detection zone right around the door and keep the sensitivity and threshold high enough that I'm not getting a bunch of false alarms, but make sure it still detects when I walk by the door. This way, if an intruder walks up to the door it will alert me, but I'm not covering a large area that has the potential for a lot of false alarms.
3. I have my anti-dither set as low as possible. Not sure what it does but I think you get better snapshot of the actual movement the lower it is. I actually have my snapshot set to send 5 snapshots but I can only get it to send me one. Not sure how to get that to work right. In the email settings, it has a delay as well. For this one, if you set to 30 seconds, you will get one email for a motion, but won't get another alert for more motion until 30 seconds has passed from the first alert.
The best advise I can give is keep increasing your sensitivity and threshold levels and testing that out and/or select smaller areas of motion detection so that your now covering so much area. I haven't really tried just setting both levels high and covering the whole screen but maybe that would allow for only major movement like whole person to set it off instead of small objects like leaves.
The whole system is confusing and the manual doesn't have good definitions of what all the stuff does but if you just keep trying different settings you can somewhat get where you need.
Re: Motion Detection Sensitivity / snapshot of MD trigger
The snapshot is triggered my motion detection with a default timing of 4 seconds before the trigger event. I went to SETTINGS/SCHEDULE/STORAGE/RECORD and changed the PRE-RECORD setting from 4 seconds to 0 seconds. This will time the snapshot with the actual trigger event. Otherwise the snapshot is taken 4 seconds before the trigger event, usually showing nothing. The down side is that your video will also start with the trigger event and won't show what happened the 4 seconds prior.
Re: Motion Detection Sensitivity / snapshot of MD trigger
Brandon -
thanks for your thoughts - I'll continue to tinker and let you know if I hit upon anything that solves the issue.
As for the sensitivity and threshold settings - is a higher number more sensitive, or less sensitive?? I've been ratcheting both numbers lower thinking that I am turning down the sensitivity - are you working in the same direction?
do you have any ideas what the 'threshold' setting is actually doing? my thinking is that it would be looking to determine how significant the movement is within the detection zone, but as you say, the manual doesn't give much detail, and I'm just guessing.
I have had some success playing with the anti-dither. what I've found is that it's a delay timer between alerts. I've got mine set to 300 currently (5 minutes), in the thinking that if a person actually enters the detection zone, I only need one picture of them, the video will take care of the rest. on the other hand, if there is snow or a blowing branch that is triggering, I will only get one alert every 5 mins max. I suppose there is some risk that a person will enter the detect zone within the 5 minute period after a branch or snowflake sets it off, and I'll miss them - but until I can get the sensitivity figured out, I am way too many alerts, and setting this higher has reduced the number some.
thanks for your thoughts - I'll continue to tinker and let you know if I hit upon anything that solves the issue.
As for the sensitivity and threshold settings - is a higher number more sensitive, or less sensitive?? I've been ratcheting both numbers lower thinking that I am turning down the sensitivity - are you working in the same direction?
do you have any ideas what the 'threshold' setting is actually doing? my thinking is that it would be looking to determine how significant the movement is within the detection zone, but as you say, the manual doesn't give much detail, and I'm just guessing.
I have had some success playing with the anti-dither. what I've found is that it's a delay timer between alerts. I've got mine set to 300 currently (5 minutes), in the thinking that if a person actually enters the detection zone, I only need one picture of them, the video will take care of the rest. on the other hand, if there is snow or a blowing branch that is triggering, I will only get one alert every 5 mins max. I suppose there is some risk that a person will enter the detect zone within the 5 minute period after a branch or snowflake sets it off, and I'll miss them - but until I can get the sensitivity figured out, I am way too many alerts, and setting this higher has reduced the number some.
Re: Motion Detection Sensitivity / snapshot of MD trigger
Hi guys, I'm going through the same exact issues as you are. Setup alerts for the first time this weekend and got hundreds of false positives. I'll do some testing myself, but would appreciate if you shared anything you find out!
Re: Motion Detection Sensitivity / snapshot of MD trigger
Hello,
First to clear up the difference between Threshold and Sensitivity. Threshold is how much the pixel change is required for it to be considered motion. Sensitivity is how much motion is required to trigger the alarm. For the Sensitivity setting, the higher the number, the more sensitive. For the Threshold setting, the higher the number, more pixel change required to be considered motion. This is useful in eliminating false positives caused by things like snow, rain, leaves, etc.
To ensure the camera takes a snapshot at the right time, in the Setting>Camera>Encode>Snapshot, make sure the Mode is set to Trigger. You can change the name of the file against the time stamp on the picture to measure if it is taken at the correct time. This is what I discovered during my testing.
The anti-dither setting is how long the system waits for no motion to be detected before ending the alarm. If motion is detected in this anti-dither time the timer resets once no more motion is detected. If motion is detected after the anti-dither time, a new alarm is triggered.
First to clear up the difference between Threshold and Sensitivity. Threshold is how much the pixel change is required for it to be considered motion. Sensitivity is how much motion is required to trigger the alarm. For the Sensitivity setting, the higher the number, the more sensitive. For the Threshold setting, the higher the number, more pixel change required to be considered motion. This is useful in eliminating false positives caused by things like snow, rain, leaves, etc.
To ensure the camera takes a snapshot at the right time, in the Setting>Camera>Encode>Snapshot, make sure the Mode is set to Trigger. You can change the name of the file against the time stamp on the picture to measure if it is taken at the correct time. This is what I discovered during my testing.
The anti-dither setting is how long the system waits for no motion to be detected before ending the alarm. If motion is detected in this anti-dither time the timer resets once no more motion is detected. If motion is detected after the anti-dither time, a new alarm is triggered.
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DanNeumann
- Posts: 35
- Joined: Sat Feb 28, 2015 5:13 pm
Re: Motion Detection Sensitivity / snapshot of MD trigger
Has anyone found a happy place for the Threshold and Sensitivity settings to eliminate triggering by cloud shadows, bugs, etc? I still have my settings at the default level but I swear an ant on the ground will trigger motion. 
And what exactly is the snapshot. Does it take an actual still picture at the first alam trigger? Where is that file saved to?
The manual tends to be a bit vague IMO on some of these subjects.
And what exactly is the snapshot. Does it take an actual still picture at the first alam trigger? Where is that file saved to?
The manual tends to be a bit vague IMO on some of these subjects.
Re: Motion Detection Sensitivity / snapshot of MD trigger
So it sounds to me like Threshold would be more to do with the size of the object moving, and sensitivity more to do with how much it has to move to trigger the alarm. So the higher the threshold the more things you can eliminate like leaves or small animals and the sensitivity would maybe be like a big branch on a tree, if sensitivity is low enough, the branch slightly swaying in the wind wouldn't set it off. That's all just a guess, I think you just have to keep tweaking it to you can get it where you want.
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DanNeumann
- Posts: 35
- Joined: Sat Feb 28, 2015 5:13 pm
Re: Motion Detection Sensitivity / snapshot of MD trigger
Something else I'd like to understand. When setting the Region on the Motion Detect tab each camera has 4 regions with a different color identifiers. Red, Yellow, Blue and Green. What are these individual ones for? Do I set the Threshold for Motion using the Yellow region? or the red where the Sensitivity is? Yellow, Blue and Green only show a Threshold setting.
Re: Motion Detection Sensitivity / snapshot of MD trigger
Amcrest -
thank you for the reply - to clarify & confirm:
Threshold is the activity (pixel change) that is required for an action to be considered motion, and as such, the HIGHER the number we set threshold to, the more pixel change will be required to qualify as motion.
conversely, sensitivity is the is the amount of motion required to trigger an alarm, so if I'm getting too many alarms, I should LOWER the sensitivity setting.
Obviously there is still some tweaking to be done, but if I'm understanding correctly, that's hugely helpful.
I'm going to try upping my threshold settings and lowering the sensitivity and will advise if that removes some of the false alerts I'm getting.
@DanNeumann -
based on the above, it would seem that the multiple color zones are designed so you can have different trigger areas with different thresholds - all will alarm at the same sensitivity setting, but you can setup the system to detect pixel change based on different threshold settings for different motion detect regions. (pretty cool actually...)
thank you for the reply - to clarify & confirm:
Threshold is the activity (pixel change) that is required for an action to be considered motion, and as such, the HIGHER the number we set threshold to, the more pixel change will be required to qualify as motion.
conversely, sensitivity is the is the amount of motion required to trigger an alarm, so if I'm getting too many alarms, I should LOWER the sensitivity setting.
Obviously there is still some tweaking to be done, but if I'm understanding correctly, that's hugely helpful.
I'm going to try upping my threshold settings and lowering the sensitivity and will advise if that removes some of the false alerts I'm getting.
@DanNeumann -
based on the above, it would seem that the multiple color zones are designed so you can have different trigger areas with different thresholds - all will alarm at the same sensitivity setting, but you can setup the system to detect pixel change based on different threshold settings for different motion detect regions. (pretty cool actually...)