is this true?

[harris7]

From the Wiki article
" Cannabis has higher reflectivity at certain wavelengths than other rural crops, such as corn. Law enforcement agencies have found that the use of this technology has become necessary in their detection efforts because many growers hide cannabis among other plants, making detection with the naked eye difficult even from the air. These techniques are effective and difficult to defeat because a plant's reflective signature is difficult to change or mask."

http://en.wikipedia.org/wiki/Cannabi...on_and_the_law

[Hagbard Celiene]

http://hydrolab.arsusda.gov/RSinARS/...s/poster08.htm

ok, so that is the site that those fucked up graphs came from... they say that

"BRDF characterization for different species in heterogeneous situations."

http://www-modis.bu.edu/brdf/brdfexpl.html

is a site that explains what that means...


and now for something actually useful...

http://list.terc.edu/pipermail/maine...il/000786.html

"Here's yet another NASA spinoff. Originally developed to detect ice accumulation on the external tank of the shuttle, this imaging system is now being adapted for early detection of disease in crops and trees.
Please disseminate as appropriate."

"When used in this application, the multi-spectral imaging system along with the real-time processor immediately provides the user with an indication of the amount of chlorophyll in the plant's leaves," Spiering explains. "Previously, the process required the recording of multiple images of the same scene. The images were then matched and aligned with each other, processed
and then made available for display only on a computer."
--

[LIP]

Planting outside near rose bushes and the like will make it safer, as rose bushes have the same heat signiture as weed. If it's a small grow then you've got nothing to worry about, apart from nosey neighbours, large amounts are obvious though.

[harris7]

The high power lights that the dopers use to grow the drugs generate a large amount of heat. The criminal farmer must vent this heat or the plants will get to hot. We can find the unusually hot exhaust pipe in the roof or the hot room in a house that seems to be hot and cold on a regular cycle (hot when the lights are on cold when they are off). taken from
http://www.predictive-maintenance.com/marijuana.html

and from http://www.predictive-maintenance.com/marijuana.html

spectral contrast between marijuana and other plant canopies appears most significant for green, red edge and short wave infrared wavelengths, however, isolation of marijuana canopy spectral signatures during land cover classification may be difficult using visible-near infrared systems

I don’t know why you are being so hostile. We agree

[mc-blaze21]

well ive just read the whole of this thread and im very impressed. we have some propper smart people amongst us. either that or just too much time on there hands but either way im still impressed. what is it they say u learn something new every day well i think ive learnt enough for a week in this one thread lol. i hope i find alot more discussions like this on here there very informative thank you all even the bloke that made the wise crack at the beggining u no the one kp bitch slapped down lol laters people peace out!

[harris7]

Well I donâ??t want to confront all the misinformation in this thread.

But I will say plants do give off heat. But that isnâ??t the heat we are talking about

I was speaking with a cannabis rights lawyer friend of mine about using infrared detection to find house grow ops.

And GOOD NEWS

It is currently illegal to use these At all in the US on houses
And in Canada they need a Warrant.
As it is considered a search of the premises

But then again whats stopping cops from doing it, detecting you, then watch you till they have â??legalâ?� evidence
and well they like to change laws and not tell us. so how long will this be true

[nitepharmer]

cool thread
what I have read at other grow forum sites is this. Chopper or plane flyovers in the fall happen only in those areas popular to outdoor growing. There are high technology ways to detect marijuana but they cost a fortune and from what I can gather are primarily used in drug interdiction efforts in foriegn countries. The tried and true method that the police use in the United States to find outdoor weed are spotters looking for its distinctive color and christmas tree shape. Not many plants are that bright bright green of marijuana, expecially late in the season. Trained eyeballs is still the best technolgy for finding small grows. The NORMAL site has a list of outdoor marijuana grow busts per state, I think its like five years out of date, but it kind of confirms what I'm saying about the police only doing flyovers in certain areas. There were 7000 outdoor busts in Tennessee and only 29 in Iowa. Any of you hiilbillys want to move?i

[growinforthefuture]

cannabis is not native to a large range of the area it is illegally grown in. In its native habitat it has an infrared color much like that of other herbaceous plants in the area. In higher latitudes a cannabis plant sticks out like a sore thumb. I know all about this stuff, because i work with satellite photos.. We take an infrared satellite image and assign the wavelengths of infrared light, visible colors. Just as cannabis has a bright green distinctive color in the visible spectrum it also gives off a unique color of infrared light.

[growinforthefuture]

btw we do this for tree counts/biology, monitoring urban development and agriculture (for example the mount of certain types of fertilizers can be monitored with infrared.) In fact I mainly deal with archaeological WE DO NOT LOOK FOR GROWS we got like 5 meter resolution anyhow, so to even appear as a pixel a pot plant would have to be the better part of 5 m^2.