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[dave w]

I'm the one making wrong assumptions??? 

Yep. You are.
And the fact that you have not been able to to do what you want to do, should confirm that fact to you.

Ambient temperature and other environmental factors will effect the "visibility" of the heat source target to the sensor. It will effect depth of field, and it will effect width of field. If a heat source is nearly invisible to the sensor, the heat source will be able to move farther into the field FROM ANY DIRECTION before the sensor will trigger. Continue to deny that all you want, it's becoming humorus.

I suggested the IR movie light source, but like I said, the perimeter you are able to define will only be true for the IR movie light.

[MD Corie]

OK. I got it now.

I'll agree with you. Physics is broken. 

Call your local reality inspector and have him run a standard testing sequence to work out exactly why radiant heat patterns do not work the same way as visual light patterns in your locale. I'm sure that when you speak to him he'll bring several friends with white jackets. It's likely his friends will bring you a special coat with the fastenings down the back and extra long sleeves with strings on the ends 

Last time I needed to get reality adjusted, it got pretty expensive - you may find it a lot less expensive to just move.

If you want to talk psychology, then this whole discussion is giving me deja vu of ENGR PSYC 101... and also reminding me of the old theory about the psychology of why some people become liberals while others become conservatives...

[MD Corie]

I'm the one making wrong assumptions??? 

Yep. You are.
And the fact that you have not been able to to do what you want to do, should confirm that fact to you.

Ambient temperature and other environmental factors will effect the "visibility" of the heat source target to the sensor. It will effect depth of field, and it will effect width of field. If a heat source is nearly invisible to the sensor, the heat source will be able to move farther into the field FROM ANY DIRECTION before the sensor will trigger. Continue to deny that all you want, it's becoming humorus.

I suggested the IR movie light source, but like I said, the perimeter you are able to define will only be true for the IR movie light.

Golly, it's nice that people are finding humor in this...  at my expense.

But I gotta say once again that folks are making up their own assertions, and attributing them to me, when I myself made no such claims.  Case in point:  I've never denied that a weak IR source will be (much) more difficult to detect than a strong one!  In fact, The whole point of the question in my original post here was to find out what can be used (as a strong IR source) in order to get around that very problem and produce reliable detections, in order to map the areas that the detectors can "see".  Or, perhaps more relevantly, the areas that they don't ever see.  (I fail to see what I am "denying" in that... nor why it is so hard to get that point across!)

Regarding a movie light source, I apologise if you suggested that, but I must have missed it.  But I do not know what an IR movie light source is... and I'm pretty sure I don't have one laying around here.   Sarcasm aside, I was really hoping there might be some sort of common "household item" that would work, although I'm drawing a blank because nothing that comes to mind has worked at all.

Also, I fail to understand why a perimeter that is determined via a strong (enough) IR source would vary for some other source;  Is there some physics to "bending" (or refracting?) IR that I'm unaware of?  (If so, please explain... It sounds like it would be useful for something like stealth camoflage!)

[dave w]

I fail to understand why a perimeter that is determined via a strong (enough) IR source would vary for some other source;  
I've never denied that a weak IR source will be (much) more difficult to detect than a strong one!

You talk in circles! You can't have it both ways.

Regarding a movie light source, I apologise if you suggested that, but I must have missed it.  

Here:
http://www.simaproducts.com/products/product_detail.php?product_id=615
But you might want to read my December 21, 2011, 07:26:16 AM comment, because it is still true.

[MD Corie]

I fail to understand why a perimeter that is determined via a strong (enough) IR source would vary for some other source;  
I've never denied that a weak IR source will be (much) more difficult to detect than a strong one!

You talk in circles! You can't have it both ways.

Circles?    Clearly, something is getting lost in the translation - because I get the same feeling.

If one uses an IR source that is strong enough to ensure triggering whenever it moves within the field of view of the sensor (and -presumably- cannot trigger the sensor when the source is moving outside of the sensor's field of view) then how could an even weaker IR source trigger the sensor when such source is outside of the sensor's field of view?  That makes no sense... unless the IR somehow can bend or be refracted or something that I'm not understanding, such that the sensor is able to detect stuff that is outside of its physical boundaries.  It sounds like you're saying that the sensor somehow is capable of picking up IR from virtually anywhere around it...  and I'm not seeing how that can be physically possible.  Please, enlighten me.

[beelocks]

I think I've adequately attempted to explain but since the explanations seem to be confusing, I'll try the simple route with your original questions...

So, my question is:  Is there any more effective, more definite/reliable, and less time-consuming, method for getting a motion sensor "aligned" to the desired detection area - so that it reacts properly to any motion in the desired area, while ignoring all motion outside of that area?

No.

Also, what is the best/most reliable way to induce triggering in order to test the alignment?  (I've simply been wandering around in the desired area, and this does not seem to produce consistent results in any way, shape, or form,

There is none. You're doing exactly what the professionals do.

so I'm wondering whether there is something -maybe a light or reflector?- that I should use in order to get definite triggering results).

Nope. The very nature of PIR detectors is that they give different results under different heat and light variances. They also give different results depending on the size and heat of the subject detected. You may get different field results simply by wearing a different jacket when you re-run the same tests. You may get a different result if you wear or don't wear a hat.

Remember, in the land of the blind, the one-eyed man is king.

I sure would appreciate any/all helpful hints, because I'm thoroughly frustrated by my attempts to date.

Thanks in advance!

You're welcome 

[dave w]

Please, enlighten me.

Nope.
I supplied a URL for a strong IR source that you can use to define your perimeters. Which is what you were originally asking for. Buy it, define your perimeters, and enlighten yourself.

[MD Corie]

I think I've adequately attempted to explain but since the explanations seem to be confusing, I'll try the simple route with your original questions...

...

so I'm wondering whether there is something -maybe a light or reflector?- that I should use in order to get definite triggering results).

Nope. The very nature of PIR detectors is that they give different results under different heat and light variances. They also give different results depending on the size and heat of the subject detected. You may get different field results simply by wearing a different jacket when you re-run the same tests. You may get a different result if you wear or don't wear a hat.

...

Well, please believe me when I reiterate that I certainly do understand the variations of detection under assorted conditions and over time.  I accepted that as a foregone conclusion, due to experience, long before I ever posted my question.  One of the things that I don't understand is why people feel this is a significant issue for the mapping process - which is done over one brief period of time with one specific IR source, both of which should minimize the opportunity for variances to occur.  My expectation would be that if the IR source used is definitive enough to force triggering, it would indeed be possible to roughly determine the lines that divide the areas that the sensor can "see" from those areas that are hidden from the sensor.  If there is actually some reason why this would not occur, I've yet to read a plausible explanation of why.

Note that I fully realize that it is not practical to determine the boundary in terms of depth of field, and I'm not seeking to identify what areas within the field of view are "sweet spots", or are sensitive to particular types of targets, or anything of that nature;  I only want to find out the physical limits of the regions where the sensor could see any IR source under any conditions.  My belief is that if the mapping is done under optimum conditions, using some target that the sensor will no foolin' react to under those conditions, then it ought to be possible to distinguish where the sensor can "see" and where it is "blind".  And my sincere hope is that there is such a source that can be had without breaking the bank.

One other thing that escapes me is why it is that I cannot visually determine the boundaries of the sensor by walking in and out of the field and noting the spots where I stop being able to see the lens of the sensor around some limiting obstruction - such as a masking object.  If anything, it seems this should be a conservative determination of the blind area, because the unmasked lens is visible well past the 45 degrees from center that is specified as the sensor's physical limit of detectable area, which implies that the entire lens does not need to be hidden from view in order for that observation point to be out of the detectable area.  Again, I don't see the reason.

[beelocks]

<sigh> 

[dave w]

 

[MD Corie]

<sigh> 

Yeah, well it seems to me that I'm talking to a wall...

[beelocks]

With regard to speaking to a wall, I think you should try it.

Perhaps if you stand and talk to the wall for long enough it will come up with what you need. On the other hand, the wall may also get pissed off and walk away.


This one's all yours now Dave, I'm gonna make like a wall and leave. 

[MD Corie]

With regard to speaking to a wall, I think you should try it.

Perhaps if you stand and talk to the wall for long enough it will come up with what you need. On the other hand, the wall may also get pissed off and walk away.


This one's all yours now Dave, I'm gonna make like a wall and leave. 

I'm sorry if you feel I am pig-headed, but much of what has been claimed and suggested here flies in the face of what I've learned in school and through experience, so I was trying to reconcile those discrepancies.  Apparently, that's not to be.  <sigh>

[dave w]

In this thread, there are three pages of you, in effect, saying "no, I don't believe you". So take your experience and what you've learned in school and fix your problem.

[MD Corie]

In this thread, there are three pages of you, in effect, saying "no, I don't believe you". So take your experience and what you've learned in school and fix your problem.

If that's what it seemed, then I apologise for giving that impression.  I was trying to convey that it did not make sense (in the context of my knowledge and experience), so I was hoping someone would elaborate so as to explain the discrepancy.  In other words, to give someone an opportunity to correct my allegedly "faulty" understanding.  Since that did not happen, I can only assume my understanding was actually correct.

Please understand that I have already wasted big bucks cumulatively on this project due to taking other people's unsupported claims at face value - even though against my learning and experience - because those people were in a position where they should know what they were talking about, but obviously in retrospect they did not.  So, I'm now extremely reluctant to go with anything that seems inconsistent, until those inconsistencies can be cleared up;  consequently I try to discuss the reasoning in hopes of resolving any misunderstandings.  It's frustrating that nobody seems willing to do that... or else they are not understanding my concerns.