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Posted: 8/5/2014 2:21:07 PM EDT
There's an image in another forum where I'm a member of. It's not a technical forum and most have no experience or understanding of how NV and Thermal technologies work. The image in question (below) clearly shows a shadow of the shooter, gun and all, if you look closely. It's obviously NOT shot through a thermal imaging device but rather looks more like an image manipulated to resemble or represent what thermal looks like -- and aside from the shadow it looks pretty damn convincing.

Unfortunately, this image has many believing -- contrary to the correction of others -- that shadows actually do register on a thermal imager. I only bring this up because it underscores how otherwise innocuous information can be misappropriated / misused to "prove" something it was never intended for -- which is standard fare for the internet.

The "offending" image:
Link Posted: 8/5/2014 2:41:45 PM EDT
Link Posted: 8/5/2014 2:55:56 PM EDT
Maybe he was laying prone just before kneeling and so his heat signature was still on the pavement.

Link Posted: 8/5/2014 3:03:54 PM EDT
Link Posted: 8/5/2014 3:15:00 PM EDT
[Last Edit: 8/5/2014 3:16:02 PM EDT by SachalATN]
Link Posted: 8/5/2014 3:16:55 PM EDT
[Last Edit: 8/5/2014 3:28:01 PM EDT by TNVC]
Link Posted: 8/5/2014 3:18:32 PM EDT
Link Posted: 8/5/2014 3:20:18 PM EDT
If this was taken in full sun, and the guy held that pose for a few seconds, he would cast a "shadow".

I think that's a photoshop false color image though.
Link Posted: 8/5/2014 3:27:04 PM EDT
Link Posted: 8/5/2014 3:31:58 PM EDT
[Last Edit: 8/5/2014 3:34:12 PM EDT by TNVC]
Link Posted: 8/5/2014 3:35:23 PM EDT
Link Posted: 8/5/2014 3:40:31 PM EDT
[Last Edit: 8/5/2014 3:44:31 PM EDT by TNVC]
Link Posted: 8/5/2014 3:53:36 PM EDT
Link Posted: 8/5/2014 3:54:26 PM EDT
Link Posted: 8/5/2014 3:57:13 PM EDT
Link Posted: 8/5/2014 4:03:11 PM EDT
[Last Edit: 8/5/2014 6:46:41 PM EDT by UNV]
Link Posted: 8/5/2014 4:07:06 PM EDT
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Originally Posted By HuntTXhogs:
Maybe he was laying prone just before kneeling and so his heat signature was still on the pavement.

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So I was right, give me a prize
Link Posted: 8/5/2014 4:12:16 PM EDT
[Last Edit: 8/5/2014 4:12:36 PM EDT by UNV]
Link Posted: 8/5/2014 4:21:27 PM EDT
[Last Edit: 8/5/2014 4:37:06 PM EDT by TNVC]
Link Posted: 8/5/2014 4:26:04 PM EDT
Thermal "shadows" show up all the time. You normally see them where large stationary objects block the sun and make a cool spot on the ground.

I'm pretty sure this isn't a thermal shadow though. There's a few other tell tale signs in the image that make it look like false color. The road he's squatting on would likely be hotter than him if this was in the sun, and if there wasn't any sun there wouldn't be a thermal shadow.

Also, his clothes etc are way too hot looking.

This is an image made to give the viewer an idea of what thermal might look like, but it probably wasn't taken with an actual thermal imager.
Do we really care?
Link Posted: 8/5/2014 4:27:25 PM EDT
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Originally Posted By TNVC:


I did not miss ANY points...Glad you showed up. The point I was also trying to make is we have a SPECIFIC LINKS POSTED HERE of companies showing a pic of a COTS that has NOTHING to do with a FLIR device, and folks watermarking ownership of another supposed company. No ignorance here on how a thermal works in the field and not sure what your thread lock timer means.

Edit, yes we can talk about shadows with a I^2 device see's at night and I am sure I'm not the only one that knows about this nor would I think others would not know about this.
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Originally Posted By TNVC:
Originally Posted By UNV:
Originally Posted By HuntTXhogs:
Originally Posted By HuntTXhogs:
Maybe he was laying prone just before kneeling and so his heat signature was still on the pavement.



So I was right, give me a prize
I can't verify anything about that pic other than that a shadow in a static thermal image is plausible. Real? There is no way for me to tell. All I'm saying is that this accusation is based on ignorance to how thermals work in the field. Now, yall get back to it I was enjoying the thread lock timer!


I did not miss ANY points...Glad you showed up. The point I was also trying to make is we have a SPECIFIC LINKS POSTED HERE of companies showing a pic of a COTS that has NOTHING to do with a FLIR device, and folks watermarking ownership of another supposed company. No ignorance here on how a thermal works in the field and not sure what your thread lock timer means.

Edit, yes we can talk about shadows with a I^2 device see's at night and I am sure I'm not the only one that knows about this nor would I think others would not know about this.


Wait, I'm confused....

My prize is a Thread Lock Timer

WTF???
Link Posted: 8/5/2014 4:32:51 PM EDT
UNV that's what I was thinking. If you are stationary wouldn't the ground your shadow covered be cooling? So I go outside and view the side of the house. Then I hold my hand six inches way from the wall 20-30 seconds. View it again and guess what I see? If I had a means to record I would show you.
Not that I am claiming the above photo is or isn't real.
Link Posted: 8/5/2014 4:53:21 PM EDT
Reflections do also.
Link Posted: 8/5/2014 5:40:50 PM EDT
Oh, TheHorta.
What a party pooper.
Next thing, you'll be saying the guy's hotspots are in all the wrong places.
Link Posted: 8/5/2014 5:44:38 PM EDT
That settles it... I'm the Master of Disaster.

Just a pot-stirring Bass Turd.
Link Posted: 8/5/2014 5:49:18 PM EDT
[Last Edit: 8/5/2014 5:54:12 PM EDT by TNVC]
Link Posted: 8/5/2014 6:26:22 PM EDT
[Last Edit: 8/5/2014 6:52:34 PM EDT by SkyPup]
Just say "No" to thermal shadows!

Since a microbolometer is just measuring the surface temperature of an object and receiving its thermal emissivity signature, there is absolutely no way that a human being is going to affect the temperate of solid concrete sidealk or an asphalt road or the grass on the ground adjacent to them as they are walking by it.
Link Posted: 8/5/2014 7:44:54 PM EDT
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Originally Posted By SkyPup:
Just say "No" to thermal shadows!

Since a microbolometer is just measuring the surface temperature of an object and receiving its thermal emissivity signature, there is absolutely no way that a human being is going to affect the temperate of solid concrete sidealk or an asphalt road or the grass on the ground adjacent to them as they are walking by it.
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Dang it, so I was wrong.

This thermal gig is a wicked roller coaster to be on
Link Posted: 8/5/2014 7:56:39 PM EDT
I have taken a number of photos like that through a normal DSLR with appropriate filters for infrared. It takes some digital post-processing to reconstruct the image, but you can get a real indication of infrared reflection, etc. Because some visible-spectrum phenomena still apply in that region, you will still get shadows, etc., but not exactly a reflection of a real-time heat signature the way you would from a true thermal optic.

FWIW, taking pictures like that is relatively easy, but exposure times for most cameras are extremely long. This can be done with most DSLR sensors.
Link Posted: 8/5/2014 8:03:55 PM EDT
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Originally Posted By RocketmanOU:
I have taken a number of photos like that through a normal DSLR with appropriate filters for infrared. It takes some digital post-processing to reconstruct the image, but you can get a real indication of infrared reflection, etc. Because some visible-spectrum phenomena still apply in that region, you will still get shadows, etc., but not exactly a reflection of a real-time heat signature the way you would from a true thermal optic.

FWIW, taking pictures like that is relatively easy, but exposure times for most cameras are extremely long. This can be done with most DSLR sensors.
View Quote


The difference between a dSLR and a thermal imager is that the dSLR is actually receiving "light" in the IR spectrum (like a NOD, etc) and not thermal emissivity as with a microbolometer -- as I understand it.

Essentially, they're two different things, AFAIK.
Link Posted: 8/5/2014 9:27:13 PM EDT
Looks like the typical doctored thermal pictures you see online from various companies... Those pictures were on the SPI page? Pfft no wonder...

Unless you see those pictures on an actual FLIR website then I don't believe that chit. Being that those pictures are attached to anything with SPI on it, it doesn't surprise me.
Link Posted: 8/6/2014 3:34:23 AM EDT
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Originally Posted By TheHorta:


The difference between a dSLR and a thermal imager is that the dSLR is actually receiving "light" in the IR spectrum (like a NOD, etc) and not thermal emissivity as with a microbolometer -- as I understand it.

Essentially, they're two different things, AFAIK.
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Originally Posted By TheHorta:
Originally Posted By RocketmanOU:
I have taken a number of photos like that through a normal DSLR with appropriate filters for infrared. It takes some digital post-processing to reconstruct the image, but you can get a real indication of infrared reflection, etc. Because some visible-spectrum phenomena still apply in that region, you will still get shadows, etc., but not exactly a reflection of a real-time heat signature the way you would from a true thermal optic.

FWIW, taking pictures like that is relatively easy, but exposure times for most cameras are extremely long. This can be done with most DSLR sensors.


The difference between a dSLR and a thermal imager is that the dSLR is actually receiving "light" in the IR spectrum (like a NOD, etc) and not thermal emissivity as with a microbolometer -- as I understand it.

Essentially, they're two different things, AFAIK.


That's my understanding as well.
Link Posted: 8/6/2014 3:52:08 AM EDT
The only way to create a good thermal shadow is to take a reverse "thermal negative"


Have someone stand adjacent to a concrete building, bridge, sidewalk, whatever and situate them about 1,000 to 1,500 meters from the epicenter of a 15-25 kiloton thermonuclear device, detonate the device and the thermal heat blast will instantly vaporize their body leaving a nice "thermal negative" burnt into the concrete....


Here is a reverse thermal heat shadow from Hiroshima:






Link Posted: 8/6/2014 5:59:16 AM EDT
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Originally Posted By SkyPup:
The only way to create a good thermal shadow is to take a reverse "thermal negative"


Have someone stand adjacent to a concrete building, bridge, sidewalk, whatever and situate them about 1,000 to 1,500 meters from the epicenter of a 15-25 kiloton thermonuclear device, detonate the device and the thermal heat blast will instantly vaporize their body leaving a nice "thermal negative" burnt into the concrete....


Here is a reverse thermal heat shadow from Hiroshima:


http://mastersofmedia.hum.uva.nl/wp-content/uploads/2008/03/hiroshima-shadow-2.png


https://fbcdn-sphotos-d-a.akamaihd.net/hphotos-ak-xfp1/v/t1.0-9/969508_457858310964521_748187621_n.jpg?oh=e22d402168289b81a3f3280a659ae580&oe=543ED398&__gda__=1414517386_de5b236b9f1d4a7307e77001b9813e35
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Seems like an awful lot of work to make a shadow appear in a picture, kinda makes me leary of ever offering to pose as a thermal model now that you mention this.
Link Posted: 8/12/2014 10:25:50 AM EDT
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