Windy Day Question

shrtcirkt

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I was out today testing a cam getting it ready to put out before Turkey season and I noticed something odd.
It'a about 35 degrees and sunny out and wind is blowing pretty good. Gusting up to about 40MPH. I noticed my cam going off without anything in front of it.
It's clear for about 60' around the camera, whith the sun behind it.

Has anyone else had any experience with how their camera's react during windy conditions, is this normal or do I have a possible problem?
TIA...
 

LW

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shrtcirkt,
Notice the small pine in the foreground under the feeder leaning right, then the pines in the background leaning left
I only had 2 like this on that roll and nothing else but that indication of swirling wind, also my cam was attached to a small pine that was probably moving too.

 

Applbit

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I hope it doesnt or ill have a bunch of pics of nothing.:frown-blue: Wind gusts to 48 last time i checked!
 

Archilochus

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Hi shrtcirkt,
The wind can cause false pics under different conditions (some already mentioned):

 If the sensor is physically moved.

 If a warm object (sun-warmed shrub or leafy branch) is moved by the wind against a relatively cool background.

 If the 'new' air moving in is warmer or cooler than the 'still' air that was previously in front of the sensor.

 If the wind causes fast moving clouds to shade / expose a sun-warmed patch of ground in front of the sensor (the same can also occur if a branch or other object shades / exposes a patch of ground) .

Archilochus
 

shrtcirkt

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Thanks Everyone !!!
I feel better now, I thought I was gonna have some real problems. At least I now know to wait for a calm day to try and test a cam out as well.:)
 

Tinhorn

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I just picked up a cam Saterday and when I walked in front of it, it took my pix, turns out, that was Number 21 for the week it was out.  I was excited because I have gottin a pix of a 9 point twice in the area and was wondering if he still had head-gear.

When I got them developed I only had 5 animal pix's (me and coons) the rest were false alarms...

It was facing due North in a field with some cedars.  Every day at 13:00 to 13:30 hours (1 to 1:30pm) it snapped several pix's.  It was a very windy, but sunny week and I guess when the sun was in the exact position, along with the wind swayed trees, it sensed movement.....

Months ago, somebody used one of those Heat Sensors and discovered different trees retained heat more than others.  He said cedars were one of the worst for retaining heat and potentially causing false alarms.

It seems just a short while ago I was tired of getting all doe pix's,  now I can't buy a doe pix.   where'd they all go ? ? ?

Tinhorn
 

TNDEERHUNTER

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I picked up one of my cams this weekend and only had three deer pics and the rest were false alarms. I had it in a creek bottom facing north.One thing I noticed is that in all the false pics the sun was shining through about 15' in front of my cam. The wind has blowing all week I thought I might have a few but 21. Any Ideas from anyone how we can solve this problem?
 

Brian

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Back when I first started using the PIR sensors I was in a shop testing the output of the PIR with a oscilliscope.  Everytime the air conditioner would turn on the ambient level of the trigger voltage would rise.  When the air cut off the level would fall.  The wind and temperature definitely affect the sensitivity of the senor.  Combine that with heat and it gets worse.  Since the level is raised now your sensor is automatically more sensitive.  Throw some heat on a pine or cedar tree that is moving in the wind and you will get some false pictures.  It will not be as bad in the winter as in the summer.
The only way I have combated this is by adjusting the gain of the amplifier depending on the time of year.  This reduces your range but it also reduces the false pictures.
 

Brian

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I build my own PIR circuits and I have an adjustment POT for the gain.  Most of the premade sensors are not adjustable.  The RS sensor for example uses a specialized chip with the amplifier built in so it is not possible to adjust.  I am not famaliar enough with the MS20 to know but seems like it might be possible but I have not had a chance to dissect it.  Just from what I saw it doesn't look like it will work.
 

shrtcirkt

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Hey Brian,
What about using a Thermistor instead of a potentiometer?
Wouldnt a proper  thermistor provide automatic gain adjustment with temp changes?
 

Brian

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I guess in theory yes it would but you would have to have the right resistance with the appropriate change in resistance per degrees and that would be the most difficult to find.
I believe Jaggermax was working with a digital pot and a temperature sensor to do the same thing.  His probably was the sensitivity of the sensor vs. the temperature.  Knowing exactly how much resistance to give or take away according to the temperature. I definitely believe it would be difficult to find a thermistor that would fit but I could be wrong.  The micro controller and a digital pot is probably the easiest way to do something like this or manually turn the pot yourself like I do and then check the sensing distance.
 

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