Spectrometry
spectrometry

The Public Lab spectrometry project is an open source community effort to develop low-cost spectrometers for a range of purposes. All open spectrometry hardware and software efforts are welcome here! **Join in by:** * Learning [what spectrometry is](#Whats+spectrometry) * Reading about goals and [asking great questions](#Frequently+Asked+Questions) * Building a basic spectrometer using [one of our starter kits](#Starter+Kits) * Trying (and critiquing) our [community-made how-to guides](#Activities) and posting your own * Building on others’ work; hack and remix the kits to refine and expand them * [Share your upgrades](#Upgrades) for others to try -- and perhaps for inclusion in an upcoming starter kit release or add-on kit **** ## Starter Kits Public Lab’s Kits initiative offers several starter kits, including many of the basic components, and instructions for constructing a basic visible light spectrometer. The point of the kits is to provide a shared reference design for building experimental setups onto. Lego Spectrometer Kit Our most recent kit, incorporating community improvements while balancing low cost and ease of construction. Choose between webcam and Raspberry Pi camera versions and build attachments width standard Lego connectors. Build one Buy one Papercraft Spectrometry Intro Kit A $9 paper spectrometer which you can attach to a smartphone or webcam. It’s made of paper to reduce cost and complexity, and is mainly intended as an “introductory” or educational kit. The flat design can be printed on a laser printer or photocopied to make more. Build one Buy one **** ## Activities This is a list of community-generated guides for specific applications using your spectrometry setup (either a [starter kit](#Starter+Kits) or a [modded design](#Upgrades)). These [activities can be categorized](https://publiclab.org/wiki/activity-categories), and some may be more reproduced -- or reproducible -- than others. Try them out to build your skills, and help improve them by leaving comments. Together, we can repeat and refine the activities into experiments. > **Note:** If you are working on an **urgent issue** such as a threat to your or someone else’s health, please know that these techniques may not be ready for your use; it's possible that they never will be. [Read more here](/notes/gretchengehrke/09-29-2016/common-low-cost-technique-limitations) ### Activity grid [activities:spectrometry] **** ## Upgrades Have you added to your starter kit, improved it, or redesigned it? Show others how to take it to the next level by posting a build guide here: [upgrades:spectrometry] Add your upgrade guide here Request or propose an upgrade _Mods should include a parts list and a step-by-step construction guide with photo documentation. See an example._ **** ## Challenges We're working to refine and improve DIY spectrometry on a number of fronts; here, take a look at the leading challenges we're hoping to solve, and post your own. For now, we're using the Q&A feature, so just click "Ask a question" to post your own challenge. Be sure to add: * constraints: expense, complexity * goals: performance, use cases [questions:spectrometry-challenge] **** ## Builds There’s a lot going on in open source spectrometry -- if you’ve developed another open source design you’d like to show others how to construct, post it here! * [RamanPi](https://hackaday.io/project/1279-ramanpi-raman-spectrometer) * [Hackteria “drop”-style spectrometers](https://publiclab.org/notes/gaudi/04-03-2014/diy-micro-volume-spectrophotometer) / [DIY NanoDrop on Hackteria.org](http://hackteria.org/wiki/index.php/DIY_NanoDrop) * _Add yours here_ ##What's spectrometry? Colored light is often a blend of different colors. A spectrometer is a device which splits those colors apart, like a prism, and measures the strength of each color. A typical output of a spectrometer looks like this spectrum of the daytime sky, with the actual light spectrum at the top and the graph of wavelength (horizontal axis, in nanometers of wavelength) and intensity (vertical axis) below: [![sky.png](https://i.publiclab.org/system/images/photos/000/005/455/original/sky.png)](https://spectralworkbench.org/analyze/spectrum/19882) > Needed: overview of spectra, calibration, units, comparison, and fluorescence/absorption. Please edit this page or link to a resource, potentially [the Wikipedia page](https://en.wikipedia.org/wiki/Spectroscopy), although that's quite full of technical jargon. ## Software Spectral data can be analyzed with https://spectralworkbench.org to create spectra plots, find centers of emissions plots, and find similar spectra. Data also can be exported in various formats (JSON, CSV, XML) for further analysis and visualization. ## How does this compare to a lab instrument? The [Desktop Spectrometry Starter Kit](/wiki/desktop-spectrometry-kit-3-0) is only one part in an experimental setup, and the following shows where it fits in an overall diagram of a lab spectrometric setup: [![tmp_31873-IMG_20161027_101601_2-79757779.jpg](https://publiclab.org/system/images/photos/000/018/635/large/tmp_31873-IMG_20161027_101601_2-79757779.jpg)](https://publiclab.org/system/images/photos/000/018/635/original/tmp_31873-IMG_20161027_101601_2-79757779.jpg) [![tmp_31873-IMG_20161027_095939_2-108076392.jpg](https://publiclab.org/system/images/photos/000/018/636/large/tmp_31873-IMG_20161027_095939_2-108076392.jpg)](https://publiclab.org/system/images/photos/000/018/636/original/tmp_31873-IMG_20161027_095939_2-108076392.jpg) There are many, many different types of spectrometry and spectrometers -- many don’t even measure light. Even among those that do, some detect light in the ultraviolet range, and others in the infrared range of light. The range of Public Lab spectrometers depends on the range of the commercially available cameras we attach them to (~400-700 nanometer wavelengths). A commercially available product with a slightly wider range (from 335 to 1000 nanometers) is [available from Cole Parmer](http://www.coleparmer.com/Product/Cole_Parmer_Visible_spectrophotometer_335_to_1000_nm_wavelength_range_analog_output/UX-83055-10). **** ## Frequently Asked Questions [questions:spectrometry] Note our previous Frequently Asked Questions page, which [can be found here »](/wiki/spectrometer-faq) -- please help port these into the new system, here!...


Author Comment Last activity Moderation
warren "Hey jay - this is a great post - it seems like your camera is just extremely sensitive and is being badly blown out (or clipped) by pointing your s..." | Read more » about 10 years ago
cfastie "Hi Jay, This is a great example of how important it is to get a good exposure on spectral photos. You have to hit it just right to get the most in..." | Read more » about 10 years ago
sergsh "We are interested in such sensors for scientific work in the coastal zone of the Sea of ​​Azov. Can somebody suggest how you can buy these products..." | Read more » over 10 years ago
Becki "Sreyanth--Thanks so much for all your hard work this summer. I think the end result is absolutely amazing! I'm glad to hear you got so much out of ..." | Read more » over 10 years ago
Sreyanth "Thanks for your compliment :-) Glad you liked the new features. We came up with the present system assuming that the spectrums would be calibrated..." | Read more » over 10 years ago
straylight "Sreyanth, awesome work, I love the interface and well done on following the project through to completion. It adds a lot to the functionality of sp..." | Read more » over 10 years ago
Suiris "The test was just to measure the difference in clarity between tap water and filtered water, using a single wavelength instead of a white warm LED ..." | Read more » over 10 years ago
Ernie "I afraid that using a laser will not tell you much about the chemical composition of any contamints in your water. The laser spectrum is much too ..." | Read more » over 10 years ago
Suiris "Hi drabanus, The time span between each spectra was less than 30 seconds and the LED light had been on for quiet some time before I began the tests..." | Read more » over 10 years ago
Suiris "Hi Ernie, Thanks for the great advice and information. To be honest I am completely new to te spectrometer hobby and most of what you wrote baffles..." | Read more » over 10 years ago
drabanus "One other test to characterize the stability of your spectrometer is to just repeat identical measurements after a certain time span, say minutes, ..." | Read more » over 10 years ago
Ernie "Some typo's in my previous post: To normalize your sample spectrum, you will want (delete "you") to divide... Use an (delete "sample") empty bottle..." | Read more » over 10 years ago
Ernie "I hope your system is mechanically stable so as to get reproducible spectra. With regard to the illumination spectrum (the LED), it is not truly w..." | Read more » over 10 years ago
Suiris "I am using a Canon IXUS 120 IS for taking pictures, then I cut out the spectrum from the black background, paste it as a new image and upload it t..." | Read more » over 10 years ago
danbeavers "OK then I would like to know about your work flow. Are you using a camera attached to your computer or are you taking a picture and then processing..." | Read more » over 10 years ago
Suiris "I noticed the shift too danbeavers. My thoughts are that when I cut out the spectrum from my image and pasted it as a new image I wasn´t carefull w..." | Read more » over 10 years ago
danbeavers "I wonder about the peaks appearing to shift between different exposures. Looking at the left most peak the filtered 8 second exposure is to the ri..." | Read more » over 10 years ago
Suiris "Boiling the samples down to half their volume is a great idea! Will try that next time and see if there are any volatile contaminants. " | Read more » over 10 years ago
Suiris "Hi cfastie. Thanks! The water I tested came from the faucet in Stockholm, Sweden. The water treating plants here have a hard time filtrating medici..." | Read more » over 10 years ago
cfastie "Excellent test. What do you think is in your water? Particulate matter? Or something dissolved, like a salt? Either way, if you boiled some down to..." | Read more » over 10 years ago
warren "This looks great! Now, the tough part -- detecting enough light to get a spectrum. If you let the sample settle for a few days, does it look more c..." | Read more » over 10 years ago
sara "super exciting work! " | Read more » over 10 years ago
warren "Also, i ended up ordering those crude oil samples online: http://publiclab.org/notes/warren/05-03-2013/crude-oil-samples-for-purchase-online I'm h..." | Read more » over 10 years ago
warren "Hi Scott -- what kind of light are you using? When i've done this, i've let it settle in a clear container so I can see that all the muck has real..." | Read more » over 10 years ago