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Thermal photography

14 Nov 21:15 73,663 views | Last edited by bsugar 5 months ago | shortlink

DIY Pole Mapping Camera Mount

by Natalie about 1 month ago | 4 | 608 views | 1

What do I want to do So after my first post of DIYing it with the plastic pen caps I decided to ...

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DustDuino Data Quality

by Willie about 1 month ago | 1 | 675 views | 4

What level of accuracy can the DustDuino provide? There is an enormous need for low-cost air pol...

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Thermal Flashlight with LCD keypad display and Neopixel LEDs

by thosetechpeople 2 months ago | 0 | 457 views | 1

We added an LCD display with keypad and replaced the rgb LED with a 16 LED Neopixel ring. This wi...

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thermal-photography thermal-flashlight

Common-anode LED thermal flashlight casing and circuit diagram

by lmc6399group 2 months ago | 3 | 564 views | 2

A redrawn circuit diagram of the thermal flashlight described here: http://www.publiclab.org/wiki...

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thermal-photography thermal-flashlight thermal-camera tool

dealing with patents: Black & Decker and the Thermal Flashlight

by mathew 3 months ago | 6 | 532 views | 4

Update: actually, Black & Decker came up with this idea first and we just hadn't seen the thi...

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thermal-photography thermal-flashlight thermal-camera

Finding Hotspots With Our Thermal Flashlight

by FireLogCollective 4 months ago | 0 | 447 views | 0

We wanted to use our thermal flashlight to locate outdoor spaces which offered a significant incr...

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Thermal Camera Used For Community Mapping

by julsy709 4 months ago | 0 | 527 views | 2

Our thermal camera was used to locate significant temperature increases within an urban area in S...

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Thermal Flashlight: Tech Failure Spectacle

by acnud 4 months ago | 4 | 476 views | 3

The objective of our research project is to look for the presence of thermal pollution from the H...

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More research on "thermal-camera" »

Title Last edited Edits Pageviews Likes
Thermal photography 5 months ago by bsugar 60 73,663 1
Scanning thermal camera over 1 year ago by warren 3 15,994 0


Thermal imaging can be used to document heat/AC leaks from insulation gaps on a building's facade, reveal warmer ground water inflows (either fresh or chemical-laden) or "thermal pollution" from industrial processes entering ocean-temperature waterbodies, as well as identify areas on the human body experiencing infection or stress (includes epidemiological applications).

Community applications so far include both a "heat-busters" program in East Harlem and a "forensic" water quality monitoring program in the Gowanus Canal.


There are three prototypes in development:

  • A Thermal Flashlight (described on this page): a RGB LED flashlight with a non-contact infrared sensor that "paints" the temperature of the surface directly on the wall for capture with a second timelapse camera.
  • Thermal Fishing: dragging a thermometer through the water, taking contact measurements mapped to a RGB light, also for capture with a second timelapse camera.
  • A scanning thermal camera on a lego turntable (software also in development) that sweeps back and forth across a scene, recording the temperature variation to build up an image.


"FLIR" cameras can produce images such as the one below, and are typically used to identify heat leaks, but even low-resolution FLIR cameras can cost thousands of dollars. Our goal is to make this kind of investigation (and the potential savings) cheap, easy, fun, and informative for those of us without $10k in our pockets.

FLIR house

Thermal Flashlight

The first approach results in a kind of "light painting" -- a color heatmap overlaid directly onto the scene. This is the simplest, cheapest, and to date, most effective way we have developed of measuring heat leaks or cool leaks indoors and outdoors. Simply put, the "flashlight" puts out red light if it's pointed at something hot (default 75 deg F or more) and blue light if it's pointed at something cold *(default 60 deg F or less):

Using a Thermal Flashlight

To capture the light painting over time, we have been using timelapse photography or the prototype Public Lab Thermographer website (or its inspiration, GlowDoodle), as seen in the top image on this page.

  • Within view of the camera or laptop, sweep the flashlight beam over the scene at a distance of about 12 inches.
  • Try to stay out of the way of the beam, and don't point it directly at the camera or it will create a "starburst" and may mess up your image.
  • It's helpful to wear dark clothing so you don't show up in the image as you're moving around.

Thermal flashlight diagram

Building your own

Parts list For a Thermal Flashlight with 3.6 V Melexis Sensor and Common Anode LED.



Gist: https://gist.github.com/sdosemagen/1739961/

_Note: The goal of this file is to be a place to download everything without pursuing other links. If there are changes or updates please feel free to add and re-upload. If the file is missing anything, please comment below. You might notice that this is for the 5v Melexis, but it will work for either without issues.

Alternative variations of the Flashlight can be made with a 5.5V Melexis Sensor and Common Cathode LED. For the 5.5 V sensor follow this diagram: http://publiclaboratory.org/notes/sara/2-7-2012/circuit-diagram-5v-melexis-sensor For the common cathode circuit board follow this diagram: http://publiclaboratory.org/notes/warren/2-11-2012/common-cathode-variant-thermal-flashlight-code

Links to purchasing equipment:

Consumable Parts:

If you are starting an electronics kit from scratch:

  • a 40Watt soldering Iron (if you want it to be permanent otherwise duct tape or Velcro works temporarily)
  • hookup wire (solid not stranded- 22 or 24 gauge, you can get this at Radio Shack)
  • pliers called "wire strippers" to get the plastic wrap off the hookup wire (can get at Radio Shack)
  • solder for 40Watt iron, lead-free.
  • a breadboard (1 per flashlight). If you aren't soldering: http://www.adafruit.com/products/64. If you are soldering: https://www.adafruit.com/products/571.
  • a USB cable to connect the arduino to the computer via USB for power 5Volts (can get at Radio Shack)
  • household sponge for cleaning solder off tip
  • 9 volt battery with connector wires (can get at Radio Shack- 1 per flashlight)

Cost: ~$40-$60

These research notes will be integrated into this page to provide instructions on building and using your own thermal flashlight:

Several meetups have been organized to build and test thermal flashlights, at RISD (Providence, RI) and in Brooklyn, NY. We are organizing one now in Somerville, MA:

Thermal flashlight heatmaps

Tags: thermal-photography thermal-flashlight thermal-camera tabbed:notes tabbed:wikis tool