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Thermal photography

14 Nov 21:15 69,114 views | Last edited by bsugar 3 months ago | shortlink

Finding Hotspots With Our Thermal Flashlight

by FireLogCollective | about 1 month ago | 0 | 283 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 | about 1 month ago | 0 | 352 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 | about 1 month ago | 4 | 291 views | 3

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

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Site Visits and Results

by KKMS | about 1 month ago | 0 | 229 views | 0

For our site visits, we decided to check the heat leaks in on Memorial University campus housing....

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Thermal flashlight: data collection in Holyrood, NL

by ckenny | about 1 month ago | 1 | 327 views | 2

The aim of our research project is to examine thermal pollution at the Holyrood Thermal Generatin...

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KKMS Thermal Flashlight Project Sociology 4107

by KKMS | about 1 month ago | 2 | 233 views | 0

Thermal Flashlight Casing We decided to reuse a familiar piece of technology for the casing o...

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Arduino Uno Thermo Flashlight Casing Specs

by klrussell | about 1 month ago | 1 | 319 views | 1

The following document briefly summarizes and details the casing specs for the Arduino Thermo Fla...

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Comparison of Window Insulation in Old vs New buildings

by weertsc | about 1 month ago | 0 | 339 views | 2

What I want to do My group wanted to test whether there was a difference in the capacity of insu...

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More research on "thermal-camera" »

Title Last edited Edits Pageviews Likes
Thermal photography 3 months ago by bsugar 60 69,114 1
Scanning thermal camera about 1 year ago by warren 3 14,224 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.



_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: For the common cathode circuit board follow this diagram:

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: If you are soldering:
  • 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