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reversing the inverse square law

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The specifications for the Extreme UF500103 IR Illuminator includes the following sentence: "The unique cosec2 lens reverses the inverse square law to provide evenly distributed illumination from the foreground to background for the entire scene." Wow, that's a spectacular marketing claim.

 

Best,

Christopher

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Hahahaha, this reminds me of some of the BS I've seen in audio mags... I remember a couple in particular from many years ago in Car Audio Magazine...

 

One amp (don't recall the brand) was touting their "SCAT design" - SCAT standing for Solid Core Acoustic Technology. In short: they used solid rather than stranded wire for the internal connections. But this ad went on and on about the benefits of this design. Wow.

 

Another was for an Eclipse head unit, using optocouplers to transfer signals between the digital and analog sections. Now this has some solid basis in theory: the idea is that electrically isolating the two sections prevents digital EMI noise from bleeding into the analog circuits. The marketing hype, however, gave it some fancy name and stated in bold letters that this was a benefit because it meant "signals move at the speed of light (that's fast!)" Last time I checked, electricity moved pretty close to the speed of light, too... close enough that it really wouldn't make a difference over a distance of a few millimeters. *sigh*

 

I actually wrote to the magazine (yeah, a letter... this was in the early 90s) to call these ads out... they wrote back that they couldn't actually print my letter (can't piss off the advertisers!), but they got a good laugh out it, and sent me a T-shirt as thanks

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This declaration probably means that the IR illuminator distributes different power of radiation in dependence on the vertical angle. Thus when this IR illuminator is installed horizontally it radiates big power in the distance (upwards direction) but low power near to the illuminator (downwards direction).

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Or it just means their "cosec2" lens distributes the light differently across the area - tighter focus at the top, wider distribution at the bottom, or whatever.

 

"Reverses the inverse square law" though... what BS.

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dont know if they changed it but the ones i used, cant go within 3 feet of it when it is on or you get burned and go blind, literally. All I know is the ones I used blasted the area with a ton of light which is why it was considered a flood .. and oh yeah they cost a fortune (not so much now compared to pricing of raymax).

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dont know if they changed it but the ones i used, cant go within 3 feet of it when it is on or you get burned and go blind, literally.

 

Well then, by reversing the inverse square law, it should burn a hole through your retina at 30 feet.

 

Apparently, the inverse square law isn't really a law. It's more of a suggestion, which the photons are encouraged to follow but are free to ignore.

 

Best,

Christopher

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Like Sean, I also sell cameras with the newest firmware of flux capacitors availible on the market today. Unlike competitor's brands... all of our analog cameras come h.264 ready! Also, we are the only company who can market their ENTIRE line of cameras as license plate capture ready*!

 

 

*daytime and for parked vehicles only. 100mm lens not included. Plate must be with in 50 feet of camera and have zero backlighting. Some assembly, soldering, welding, and fire fighting skill required. Not intended for outdoor use.

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The specifications for the Extreme UF500103 IR Illuminator includes the following sentence: "The unique cosec2 lens reverses the inverse square law to provide evenly distributed illumination from the foreground to background for the entire scene." Wow, that's a spectacular marketing claim.

 

Best,

Christopher

 

Can u plz provide link to original document ,pdf

Thanks

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Everywhere I've found this unit listed uses the same copy, which would lead me to think that's what they get from the manufacturer.

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^You forgot, "Not to be taken internally."

 

Thanks for remindming me... actually these units work better if you do.

 

Believe it or not, our units have also been proven to help fight against heart disease and gingivitus**.

 

 

 

 

**possible side effects include but not limited to heart attack, tooth loss, uncontrolable and explosive bowels, pink eye, insomnia, decrease size in genitalia, a perpetual feeling of winning the lottery but then loosing the ticket, and divorce.

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So that is where they got the idea for the little illuminator pictures that are on the side of each discussion topic.

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So that is where they got the idea for the little illuminator pictures that are on the side of each discussion topic.

Yes was a popular IR back in 2003 and one of the few really powerful ones

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The specifications for the Extreme UF500103 IR Illuminator includes the following sentence: "The unique cosec2 lens reverses the inverse square law to provide evenly distributed illumination from the foreground to background for the entire scene." Wow, that's a spectacular marketing claim.

Best,

Christopher

 

Can u be plz more specific and explain your point

why u find this to be "spectacular marketing claim"

 

is this about "inverse square law" in general

 

or "reversing inverse square law" ?

Thx

just curios

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The specifications for the Extreme UF500103 IR Illuminator includes the following sentence: "The unique cosec2 lens reverses the inverse square law to provide evenly distributed illumination from the foreground to background for the entire scene." Wow, that's a spectacular marketing claim.

 

Best,

Christopher

 

actually, though they could have put it in plainer english, what they are saying (i think) is that instead of diminishing light over the distance of the scene, which is the norm, it is even light until the end of the scene.

 

How true is it though.. i dunno .. i cant really see how strong the light is in the following image at 200' away from the camera (the distance to the gate). I do recall my eyes hurting at the gate though but could have just been mosquitos

file.php?id=1792

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The specifications for the Extreme UF500103 IR Illuminator includes the following sentence: "The unique cosec2 lens reverses the inverse square law to provide evenly distributed illumination from the foreground to background for the entire scene." Wow, that's a spectacular marketing claim.

Best,

Christopher

 

Can u be plz more specific and explain your point

why u find this to be "spectacular marketing claim"

 

is this about "inverse square law" in general

 

or "reversing inverse square law" ?

Thx

just curios

"REVERSING the inverse square law" would essentially require a complete defiance of one of the most basic laws of physics. Thus, claiming to do so IS a rather spectacular feat of marketing.

 

Come on, even Scotty couldn't do it: "Cap'n, I canna change the laws o' physics!"

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Can u be plz more specific and explain your point

why u find this to be "spectacular marketing claim"

 

It may be helpful to visualize the inverse square law. Suppose you want to butter your toast with a butter spray gun. Suppose the butter spray pattern will precisely cover a single slice of toast when held one foot from the toast. Now, suppose you want to butter four slices of toast the same time. All you have to do is arrange the four slices in a 2x2 pattern and move the sprayer two feet from the toast. You have doubled the distance between the sprayer and the toast, and 1/4 of the butter is falling into each slice. That is the inverse square law. In other words, there is a relationship between the distance and the amount of butter (light) that falls on a given area. If you double the distance, you reduce the light on a given area by a factor of 2 squared which is 4. If you triple the distance, you reduce the light on a given area by a factor of 3 squared or 9.

 

This law is well known in the field of photography, and such BS would be ridiculed as a joke in photography marketing literature. Security camera manufacturers assume that security camera installers know very little about light, and much of the security camera marketing literature is near worthless. Lux ratings don't mention shutter speed or aperture, IR Illuminators give an arbitrary distance without any mention of assumed camera or lens specifications, varifocal lenses don't mention aperture for the full zoom range, and the list goes on and on. It's pathetic. Security camera installers with a background in photography don't know whether to laugh or to cry when reading these specifications.

 

Best,

Christopher

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Ill repeat what manufacturers have told me in the past, the reason why they dont list everything is that it can differ from one installation to the next, and they are saving themself from any liability. Even with Extreme they use to give distances but made note they were based on infrared optimized cameras, specifically the ones they sell, and it can differ with other cameras. DVR manufacturers say they dont provide demos as it will differ depending on cameras used, internet connection, compression, settings etc.

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Ill repeat what manufacturers have told me in the past, the reason why they dont list everything is that it can differ from one installation to the next, and they are saving themself from any liability. Even with Extreme they use to give distances but made note they were based on infrared optimized cameras, specifically the ones they sell, and it can differ with other cameras.

 

With all due respect, if you understood how to use a guide number, you would know this is BS.

 

Best,

Christopher

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Ill repeat what manufacturers have told me in the past, the reason why they dont list everything is that it can differ from one installation to the next, and they are saving themself from any liability. Even with Extreme they use to give distances but made note they were based on infrared optimized cameras, specifically the ones they sell, and it can differ with other cameras.

 

With all due respect, if you understood how to use a guide number, you would know this is BS.

 

Best,

Christopher

How is that BS? They are saying that due to the amount of different cameras in the field, they cannot tell you exactly how their product will perform, thats all - eg. there are many variations of an exview chip and they all perform different.

 

No I dont know photography "terms" as that does not pay my bills. I do however know F stops and the value of a 1.0 over a 1.4 in low light apps, and how useless slow shutter is in our industry. But as long as we are selling CCTV cameras then it is more important to know the product one sells and how it works in the real world and not on paper or how one thinks it should work.

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