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Best flood light with motion sensor to distinguish a person from wind?

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micky

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Sep 17, 2014, 12:33:55 AM9/17/14
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Best flood light with motion sensor to distinguish a person from wind?

Years ago, I bought a non-brand name device with places for 2
floodlights and a sensor to turn them on when it was dark out and motion
was sensed, which also caused a beeper in the house plugged into the AC
to beep when the sensor turned fhe floodlights on or continued to keep
them on.

I liked that beeper but I've turned the sensitivity to the lowest of 3
settings and still the wind is turning the floods on all the time. I
want to replace the fixture.


Is there a brand or model of such a floodlighht with the ability to
distinguish someone walking in my yard from the wind?


(I'm not worried about burglars much when I'm home, but if I can get my
back pain under control, I plan to go away for a month in late
February.)

Tony Hwang

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Sep 17, 2014, 12:59:47 AM9/17/14
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Hi,
Think IR sensor.

RobertMacy

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Sep 17, 2014, 2:04:45 AM9/17/14
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We have IR sensors. The wind moves our flora around and depending on the
weather, the 'moving' flora can look like people walking around and the
lights go on with nothing there. Plus, now the bats have learned to fly
around close to the IR sensors, set off the lights, then eat the bugs the
lights attracted. We have 'night vision' cameras with multiple angles of
cross coverage recording all the time, so when reviewing the HD
recordings, I watch these bats swoop back and forth until setting off the
flood lights, then the bats really go nuts with the feast that follows.

mike

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Sep 17, 2014, 4:07:03 AM9/17/14
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I did a lot of research before deciding not to implement a security
camera system.

Can't give you any specific recommendations, but I can give you a few things
to think about.

Typical low-end IR sensors have a single sensor that outputs a voltage
dependent on the total IR illumination of the scene.

Motion is detected by the curved plastic lens in front of it.
That pattern you see is many individual Fresnel lenses that focus the
IR onto the sensor. Because of the angles involved, for a given
direction, approximately one of the lenses focuses on the sensor.

As the heat source moves across the field of view, the image from one
lens passes on, then off, the sensor, then the next and so on...

It's the change in sensor output that is interpreted as motion.

You need a temperature difference that moves.
Under normal conditions, flora is the same temperature as the surrounding
area. Movement should not be detected...unless the motion of the
flora masks, then unmasks a hotter or colder region.

Depending on the construction of your particular device, you may
be able to use a laser pointer to determine which of the lens elements
focuses the problem area on the sensor and mask it out with some IR-opaque
tape. Or just reduce the sensitivity with some IR-not-quite-transparent
tape.

The bat problem is interesting. I think you're gonna have to get
clever and use more than one sensor.

One thing I can think of is to use
two IR sensors. One as you currently have and the other pointed up
toward the sky, above human range. The bats would trigger the skyward
one. Use that to inhibit the light on the other one. Should only take
a relay.

Or maybe do the same thing with an ultrasonic sensor that senses the
bat "chirps."

I know nothing about bat behavior, but if the presence of a human
scares them off, there'd be little reduction in actual security.

Would also be interesting to know if the bats are consciously
triggering the light, or if the light is a happy accident of
their normal foraging behavior.

An alternative is to use the cameras for motion detection.
The software detects motion by looking at the differences between
sequential images. There's software that lets you mask out problem
areas. But you'd be masking out all the flora, anything the wind
moves and the bat flight path. May be nothing left.

There are many variables to consider.
For me, I determined that a sign in the front yard saying,
"I don't have a big-screen TV, but my neighbor does,"
would go a long way to prevent being burgled.

A simple motion sensor light says, "It might be risky to
come here, go next door."

I don't need to stop a burglary, I just need to send it somewhere
else. ;-)

I've got several cameras. Just can't imagine that having
a fuzzy picture of a ski mask stealing my stuff...and my
camera...would be much help.

Would be interesting to see a study of burglaries by type
of prevention/surveillance...done by someone NOT motivated
to sell me surveillance equipment.


RobertMacy

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Sep 17, 2014, 10:44:25 AM9/17/14
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On Wed, 17 Sep 2014 01:07:03 -0700, mike <ham...@netzero.net> wrote:

>> ...snip....
>
> You need a temperature difference that moves.
> Under normal conditions, flora is the same temperature as the surrounding
> area. Movement should not be detected...unless the motion of the
> flora masks, then unmasks a hotter or colder region.

Used to be in the Security Industry. Very familiar with almost every
detector but the new ones that actually 'smell' an intruder and recognize
a human. And, can be placed around a location, then you go in later and
pick up your units, go through the data and determine time of day, how
many, and where they went. Don't even have to do this real-time anymore.

Anyway, I'm very familiar with the nuances of designing ultrasonic,
microwave, and IR motion detectos. In addition some types you might not be
familiar with: one that is very obtrusively a visual blight, using 10kHz
electric field androwas and rowas of interlaced send/receive conductors
all for perimeter security; and the less obtrusive one [invisible] like a
cable placed in a zig zag pattern just under the surface of the ground to
detect an intruder walking over it [picture a carpet pad type thingy; and
a perimeter security using parallel 'very leaky' transmission cables that
launches high frequency energy above the surfaceto detect motion of an
intruder. But ALL these still require some processing to determine whether
the disturbance came from an intruder, and what type, or is something else
going on, like gophers digging around. We referred to all these sensors
as, "Fai weather Detectors", because they always worked fine in fair
weather.

When I lived in a super urban area, I once put the 10kHz 'fence' small
section on the inside of a downstairs wall along an unprotected drive. One
night it went off, I went out to discover four very drunk sailors looking
for the tattoo parlor. I had to tell them that was South 600 block, not
the North 600 block, and they all toddled off but less boisterous.

After living in an urban area, I found the best [to keep Ms happy] was to
put in cameras that look AVERYWHERE, and be able to switch them into the
TV screen to 'look around' if you hear something. Her hearing is
incredible! Some details of her hearing ability are astounding. At least
with cameras she can 'look' around, safely.

> ..snip...
> Would also be interesting to know if the bats are consciously
> triggering the light, or if the light is a happy accident of
> their normal foraging behavior.

I do not know. I do know the birds have learned that I fill the birdbath,
so when it goes empty, they'll come around to the office window, opposite
side of the house, and land on the window sill to get my attention [and
glare at me] then when I go around to the breakfast bay windows where the
now empty birdbath is, the bird will stomp around inside the empty
birdbath glaring at me, and if I say nothing just stand there, they fly up
to the window, sit on the ledge look at me, look at the empty birdbath,
look at me, back and forth; as if to say, "Don't you see our birdbath is
empty!? So are gonna fill it?" Then when I go out and fill it; they'll sit
in the trees and chirp loudly, don't know if that means, "Thanks." or
"Where have YOU been?"

> An alternative is to use the cameras for motion detection.

Although possible to do, I still always set all 8 cameras for constant
recording, so I don't miss anything, just in case.

> There are many variables to consider.
> For me, I determined that a sign in the front yard saying,
> "I don't have a big-screen TV, but my neighbor does,"
> would go a long way to prevent being burgled.
>
> A simple motion sensor light says, "It might be risky to
> come here, go next door."

Rodney Dangerfield had a routine about preventing his flat being
burglarized. Somthing about putting a note on the door saying, "I'm
inside, no need to rob me" only to come back and find everything gone and
a note saying, "Stopped in, couldn't find you, so I borrowed a few things."

> I've got several cameras. Just can't imagine that having
> a fuzzy picture of a ski mask stealing my stuff...and my
> camera...would be much help.
>
Picture shouldn't be fuzzy, need a better camera. Turns out that even with
fuzzy images and masked people; someone who knows them can recognize them.
That's why they post those videos on TV News, because someone who knows
the perp will recognize them and turn them in [if really heinous crime]

Ed Pawlowski

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Sep 18, 2014, 6:10:09 AM9/18/14
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On Wed, 17 Sep 2014 00:33:55 -0400, micky <NONONO...@bigfoot.com>
wrote:

>Best flood light with motion sensor to distinguish a person from wind?
>
>Years ago, I bought a non-brand name device with places for 2
>floodlights and a sensor to turn them on when it was dark out and motion
>was sensed, which also caused a beeper in the house plugged into the AC
>to beep when the sensor turned fhe floodlights on or continued to keep
>them on.
>
>I liked that beeper but I've turned the sensitivity to the lowest of 3
>settings and still the wind is turning the floods on all the time. I
>want to replace the fixture.
>
>
>Is there a brand or model of such a floodlighht with the ability to
>distinguish someone walking in my yard from the wind?

Most do. I've never had one turn on from just the wind unless very
strong. Any tree branches in the way? Cats roaming the yard?

Mine goes on from any small animal but the only time weather does it
is during something extreme and not often. Light rain won't do it.

Art Todesco

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Sep 18, 2014, 9:21:34 AM9/18/14
to
Because I live in a mountainous area, there are always winds coming from
above that are either warmer or cooler than ambient. Plus there is
plenty of wildlife that sets off a traditional motion detector. I
finally put a cross driveway sensor pair near the front of the property.
It is about 2 1/2 to 3 feet off the ground. It doesn't get tripped by
wind or most wildlife. But it isn't plug and play. I used the Optex
units like this:
http://www.smarthome.com/weatherproof-infrared-70-ft-beam-motion-detector.html
but they are available in many places.

micky

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Sep 18, 2014, 10:40:46 PM9/18/14
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On Thu, 18 Sep 2014 09:21:34 -0400, Art Todesco <acto...@yahoo.com>
wrote:

>
>Because I live in a mountainous area, there are always winds coming from
>above that are either warmer or cooler than ambient. Plus there is
>plenty of wildlife that sets off a traditional motion detector. I
>finally put a cross driveway sensor pair near the front of the property.
> It is about 2 1/2 to 3 feet off the ground. It doesn't get tripped by
>wind or most wildlife. But it isn't plug and play. I used the Optex
>units like this:
>http://www.smarthome.com/weatherproof-infrared-70-ft-beam-motion-detector.html
> but they are available in many places.

It's a townhouse and I don't have a driveway, but I do have a fence, a
gate, and a sidewalk leading from the gate to the door. Things are so
much smaller and wireless than when I moved in, I should really think
about this. Maybe I can cut a 3x5x2 inch piece out of the pine tree
near the gate,, put a hole in the bark for the sensor eye, and glue the
tree back together again.

I could change the battery at night, when no one is around.

Maybe I could mount it 2 inches above the ground and bury the wiring,
for both the power and alarm switch.

People are tall enough to climb over the 44" fence, but I don't think
anyone would. I have a spring but no latch on the gate.

I coudl take the door light that goes on, often when someone has just
entered the gate, and somehow connect that to all the floodlights.
There's a lot to think about here.

Thanks.

micky

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Sep 18, 2014, 10:45:46 PM9/18/14
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On Thu, 18 Sep 2014 06:10:09 -0400, Ed Pawlowski <e...@snet.net> wrote:

>On Wed, 17 Sep 2014 00:33:55 -0400, micky <NONONO...@bigfoot.com>
>wrote:
>
>>Best flood light with motion sensor to distinguish a person from wind?
>>
>>Years ago, I bought a non-brand name device with places for 2
>>floodlights and a sensor to turn them on when it was dark out and motion
>>was sensed, which also caused a beeper in the house plugged into the AC
>>to beep when the sensor turned fhe floodlights on or continued to keep
>>them on.
>>
>>I liked that beeper but I've turned the sensitivity to the lowest of 3
>>settings and still the wind is turning the floods on all the time. I
>>want to replace the fixture.
>>
>>
>>Is there a brand or model of such a floodlighht with the ability to
>>distinguish someone walking in my yard from the wind?
>
>Most do. I've never had one turn on from just the wind unless very
>strong. Any tree branches in the way? Cats roaming the yard?

No cats. I think I pointed it away from branches. Maybe it's mostly
that I bought an off-brand and I should buy a quality brand, I like
the beeper and wanted to remove it from this light and put it in the
next one, but it's one piece with the very same circuit that turns the
light on.

I did find some floodlights that use dual sensors, PIR and microwave.

$100 instead of $20 to 30. But it would be worth it if I knew it would
work,

Also many of them had LED floods. They couldn't possibly be as bright
as incandescent, could they?

micky

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Sep 19, 2014, 3:24:29 PM9/19/14
to
On Tue, 16 Sep 2014 23:04:45 -0700, RobertMacy <robert...@gmail.com>
wrote:

>On Tue, 16 Sep 2014 21:59:47 -0700, Tony Hwang <drag...@shaw.ca> wrote:
>
>> micky wrote:
>>> Best flood light with motion sensor to distinguish a person from wind?
>>>
>>> Years ago, I bought a non-brand name device with places for 2
>>> floodlights and a sensor to turn them on when it was dark out and motion
>>> was sensed, which also caused a beeper in the house plugged into the AC
>>> to beep when the sensor turned fhe floodlights on or continued to keep
>>> them on.
>>>
>>> I liked that beeper but I've turned the sensitivity to the lowest of 3
>>> settings and still the wind is turning the floods on all the time. I
>>> want to replace the fixture.
>>>
>>>
>>> Is there a brand or model of such a floodlighht with the ability to
>>> distinguish someone walking in my yard from the wind?
>>>
>>>
>>> (I'm not worried about burglars much when I'm home, but if I can get my
>>> back pain under control, I plan to go away for a month in late
>>> February.)
>>>
>> Hi,
>> Think IR sensor.

Don't they all use IR? The other choice is microwave and I didn't
think any outdoor fixtures used that. (I will check what it says on the
box and check online too, but I think I'm right.)

I should admit that for my burglar alarm 30 years ago, I got one of the
first dual sensors, called Dual-Tech***, for use indoors. Both sensors
had to alert before the unit as a whole did. I wanted to be able to
leave my 2nd floor bedroom window open and still turn on the alarm when
I went out** but the wind still made the unit alert. The curtains
would blow so I weighed them down and still the unit alerted, just from
the warm breeze I figured.

OTOH, that was 30 years ago. Maybe they got it to work by now.

**But I wanted the alarm to sound if someone got a ladder and stuck his
head in the window. Eventually I disconnected that sensor, left the
window open, and figured that no one would get a ladder. And no one
did.

***I appreciate your reminding me of this. Just maybe they make
floodlights like this. Well they do make DSC LC-171 Outdoor PIR
Motion Detector Dual-Tech Sensor with pet immunity, but it's about $108
and that's just for the sensor, No floodlight fixture included.
Probably not meant to be mounted 25 feet high, also

Changed search terms, found a fixture with dual sensing. Doppler means
microwave.
http://www.homedepot.com/p/All-Pro-Precision-Plus-Doppler-Radar-270-Degree-Bronze-Motion-Activated-Security-Flood-Light-MS276RD/205349881?cm_mmc=Shopping|Base&gclid=CNGqkr7P58ACFce_7Aod91wAXw&gclsrc=ds
Combines Doppler radar with traditional PIR technology. $98
Turns lights OFF after a pre-selected time delay (1 or 12 minutes) For
98 dolllars, they should give more than 2 choices. My currrent cheap
one gives 3 choices and I picked 5 minutes.

But if I thought this worked, I'd buy it.

>We have IR sensors. The wind moves our flora around and depending on the
>weather, the 'moving' flora can look like people walking around and the
>lights go on with nothing there.

Wow. I thought that flora would not put out enough heat, if any, to
resemble warm-blooded people. (I have a roll of IR film in the
refrigerator for the last 30 years. Probably no good now. I got it for
fun and never got around to using it.)

Plus I don't really have much waveable or moveable flora in the area the
sensor looks at. I can tell the area by walking around at night.

>Plus, now the bats have learned to fly
>around close to the IR sensors, set off the lights, then eat the bugs the
>lights attracted.

Wow. They didn't do that at first? They learned to do it?

>We have 'night vision' cameras with multiple angles of
>cross coverage recording all the time, so when reviewing the HD
>recordings, I watch these bats swoop back and forth until setting off the
>flood lights, then the bats really go nuts with the feast that follows.

Now that I have CFL's in my bedroom ceiling fixture, I think it still
attracts bugs, but they are not hot enough to kill them. Not sure if
that's good or bad. At least I don't have to take off the glass shade
all the time to take out the dead bugs. Especially the dead stinkbugs.

And there are no more stinkbugs. I guess they completed their
disappearance more than 3 months ago, but I didnt' notice.

Now when part of the blanket falls on me, I don't think it's an ugly
stinkbug.
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