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Near-Infrared Camera

25 Jun 17:21 195,519 views | Last edited by warren 8 months ago | shortlink

MidOpt Dual Bandpass and Event38 filter testing

by Claytonb 8 days ago | 0 | 239 views | 0

I recently had Jason Dougherty with Midwest Optical Systems (MidOpt) send me some of their new D...

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Pencil lead works well as an electrode material in lead analysis

by JSummers 9 days ago | 0 | 224 views | 4

What I want to do This was a test to see if pencil lead can be used as an electrode material in ...

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How to calibrate infragram's Mobius camera for get accurate NDVI index?

by Parth 12 days ago | 6 | 260 views | 1

Hello, I have purchased infragram plant camera for find NDVI index of plant. I share camera's in...

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Fluorescence of tabasco sauce

by dhaffnersr 14 days ago | 0 | 279 views | 2

This is a test tube with ethyl alcohol 70% with 60 drops of Tabasco sauce and 1 drop of eosin Y ...

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Single vs. dual cameras

by cfastie 21 days ago | 1 | 423 views | 2

Above: Ned Horning taking an aerial photo of the scene for testing filters and calibration target...

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FLUORESCENCE OF 87 OCTANE GASOLINE

by dhaffnersr 21 days ago | 0 | 299 views | 0

Today I was doing some calibrating for fluorescing gasoline and oil samples My attempt and resul...

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How i was getting different captured images in presence or absence of sun light ?

by Parth about 1 month ago | 2 | 451 views | 1

Hello, I want to make infragram camera using i-ball web cam to measure NDVI INDEX.So,I had purch...

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near-infrared-camera infragram


Some Gulf Coast Use Cases for the Oil Testing kit in 2015

by eustatic about 1 month ago | 8 | 590 views | 3

What I want to do I would like to describe some problems encountered in Southern Louisiana where...

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More research on "near-infrared-camera" »


Title Last edited Edits Pageviews Likes
NDVI from the PLOTS near infrared camera 10 days ago by cfastie 35 29,876 2
Infragram Sandbox 6 months ago by liz 6 12,087 0
Infragram convertible cameras 6 months ago by cfastie 83 42,076 4
Public Lab Lesson 3: Photography in a New Light 7 months ago by gretchengehrke 15 3,961 4
Idea:80%COMPLETED-SAP project (Smart Agriculture Payload) 7 months ago by Mohamed 3 2,424 1
Infragram FAQ 8 months ago by ShintoSunrise 33 10,998 2
MapKnitter 9 months ago by Ariana16 25 37,926 45
Infragram about 1 year ago by Natalie 84 55,807 12
Interpreting infrared images about 1 year ago by aguchosolano 4 3,732 0
Photo Monitoring Plugin over 1 year ago by cfastie 12 15,042 4
Infragram Webapp Dev over 1 year ago by NickJemis 35 7,744 1
ndvi-gradients over 1 year ago by cfastie 5 6,066 5
LEAFFEST 2013 over 1 year ago by cfastie 59 9,764 2
Infragram Media over 1 year ago by warren 51 16,814 1
Infrablue white balance over 1 year ago by warren 7 7,497 1
Camera Selection almost 2 years ago by hagitkeysar 18 16,347 14
Dual Camera Kit Guide about 2 years ago by cfastie 24 15,113 0
Dual Camera Kit Software about 2 years ago by cfastie 24 9,333 0
WATERCHESTNUTS over 2 years ago by warren 43 10,402 51
GoPro over 2 years ago by gonzoearth 10 10,463 6
Near Infrared Camera history over 2 years ago by warren 3 7,340 0
iFarm 2013 over 2 years ago by cfastie 23 7,121 4
Near infrared imaging over 2 years ago by liz 11 7,057 1
LeafKam almost 3 years ago by cfastie 13 3,398 1
IRCam almost 3 years ago by warren 17 6,834 1
T-bracket Dual Camera Rig over 3 years ago by mathew 11 7,035 0
Canon A495 Tips over 3 years ago by cfastie 14 7,818 11
GMF 2 infrared camera feature over 3 years ago by mathew 13 7,154 0
Dual camera kit electronics over 3 years ago by mathew 22 7,118 1
NIR proof of concept: Trout Lily almost 4 years ago by cfastie 1 4,718 0

The Infragram Kickstarter video, a great introduction to the project.

Introduction

Vineyards, large farms, and NASA all use near-infrared photography for assessing plant health, usually by mounting expensive sensors on airplanes and satellites. At Public Lab, we've developed a Do-It-Yourself way to take these kinds of photos, enabling us to monitor our environment through quantifiable data.

Our technique uses a modified digital camera to capture near-infrared and blue light in the same image, but in different color channels. We then post-process the image (using Infragram.org) to attempt to infer how much it is photosynthesizing. This allows us to better understand and quantify how much of the available light plants are metabolizing into sugar via photosynthesis.

You can do this yourself (as with all Public Lab tools) but there is also an Infragram DIY Filter Pack available in the Public Lab Store.

We ran a Kickstarter for a version of this camera we call the Infragram. Read more about it here » Here's the video from the Kickstarter, which offers a nice visual explanation of the technique:


What is it good for?

Multispectral or infrared/visible photography has seen a variety of applications in the decades since it was developed. We have focused on the following uses:

  • Take pictures to examine plant health in backyard gardens, farms, parks, and nearby wetlands
  • Monitor your household plants
  • Teach students about plant growth and photosynthesis
  • Create exciting science fair projects
  • Generate verifiable, open environmental data
  • Check progress of environmental restoration projects
  • Document unhealthy areas of your local ecology (for instance, algal blooms)

Notable uses include this photograph of an unidentified plume of material in the Gowanus Canal (and writeup by TechPresident) and a variety of projects at a small farm in New Hampshire at the annual iFarm event. The Louisiana Universities Marine Consortium has also collaborated with Public Lab contributors to measure wetlands loss following the Deepwater Horizon oil disaster.

Here's an example of what one of our "Infragram" cameras sees (left) and the post-processing analysis which shows photosynthetic activity, or plant health (right). This picture was taken from a commercial airplane flight:

infragram

How does it work?

Camera modification: We've worked on several different techniques, from dual camera systems to the current, single-camera technique. This involves removing the infrared-blocking filter from almost any digital camera, and adding a specific blue filter.

swap.png

This filters out the red light, and measures infrared light in its place using a piece of carefully chosen "NGB" or "infrablue" filter. Read more about the development of this technique here. You can also learn more about how digital camera image sensors detect colors at this great tutorial by Bigshot.

Post-processing: Once you take a multispectral photograph with a modified camera, you must post-process it, compositing the infrared and visible data to generate a new image which (if it works) displays healthy, photosynthetically active areas as bright regions. An in-depth article on the technique by Chris Fastie (albeit using red instead of blue for visible light) can be found here.

History of the project: While we used to use a two-camera system, research by Chris Fastie and other Public Lab contributors have led to the use of a single camera which can image in both infrared and visible light simultaneously. The Infrablue filter is just a piece of carefully chosen theater gel which was examined using a DIY spectrometer. You can use this filter to turn most webcams or cheap point-and-shoots into an infrared/visible camera.

Background: satellite infrared imaging

The study of Earth's environment from space got its start in 1972 when the first Landsat satellite was launched. The multispectral scanner it carried, like the scanners on all subsequent Landsat satellites, recorded images with both visible and near infrared light. Remote sensing "scientists" quickly learned that by combining visible and infrared data, they could reveal critical information about the health of vegetation. For example, the normalized difference vegetation index (NDVI) highlights the difference between the red and infrared wavelengths that are reflected from vegetation. Because red light is used by plants for photosynthesis but infrared light is not, NDVI allows "scientists" to estimate the amount of healthy foliage in every satellite image. Thousands of "scientists", including landscape ecologists, global change biologists, and habitat specialists have relied on these valuable satellite-based NDVI images for decades.

There are public sources of infrared photography for the US available through the Department of Agriculture -- NAIP and Vegscape -- but this imagery is not collected when, as often, or at useable scale for individuals who are managing small plots.

ndvi-vis-comparison.jpg

Caption: Normal color photo (top) and normalized difference vegetation index (NDVI) image. NDVI image was derived from two color channels in a single photo taken with a camera modified with a special infrared filter. Note that tree trunks, brown grass, and rocks have very low NDVI values because they are not photosynthetic. Healthy plants typically have NDVI values between 0.1 and 0.9. Images by Chris Fastie. Visit the gallery of high-res images by Chris Fastie

How to process your images:

We're working on an easy process to generate composite, infrared + visible images that will reveal new details of plant health and photosynthesis. There are several approaches:

Note: Older versions of this page have been kept at the following wiki page: http://publiclab.org/wiki/near-infrared-camera-history


Tags: near-infrared-camera infragram list:plots-infrared tabbed:notes tabbed:wikis tool