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
eustatic "@partsandcrafts " | Read more » over 9 years ago
eustatic "https://www.flickr.com/photos/eustatic/14801633992 nail polish bottles = success. remember, the brushes are gummed. spectral workbench is har..." | Read more » over 9 years ago
WhiteRabbit "I found this: http://www.vernier.com/products/sensors/col-bta/ which is interesting because unlike other low-cost spectrometers/colorimeters its s..." | Read more » over 9 years ago
warren "Wow chris the barcode scanner filter idea is great!!! " | Read more » over 9 years ago
cfastie "The Public Lab desktop spectrometer is quite capable of making a spectral graph of sunlight reflected from grass. The curve will differ from the pr..." | Read more » over 9 years ago
WhiteRabbit "Here's a write-up that I'm finding quite helpful: http://publiclab.org/notes/nedhorning/11-01-2013/why-a-red-filter-should-work-well-for-ndvi Eyeb..." | Read more » over 9 years ago
WhiteRabbit "Sounds like gel filters would be tricky at best, so I guess ixnay to that. How about this one? http://www.ebay.com/itm/Optical-Interference-Filter..." | Read more » over 9 years ago
cfastie "I have not seen a cheap filter like Rosco that is truly a narrow band pass filter. It might be possible to combine filters to get a fairly narrow t..." | Read more » over 9 years ago
WhiteRabbit "Cool! Awesome post. I suppose it's wishful (and probably foolish) thinking, but given the the low price of a filter swatch book and the seemingly..." | Read more » over 9 years ago
cfastie "A filter switcher is a viable solution, especially for small cameras. Cameras as large as Powershots might require a big, precise device in front o..." | Read more » over 9 years ago
WhiteRabbit "Thanks, Chris, for your thoughtful and very informative post. If I'm reading it right, perhaps using two monochrome cameras, each with the appropr..." | Read more » over 9 years ago
cfastie "It should be possible to distinguish between stressed and non-stressed lawn grass using NDVI. I suspect that the $900 FieldScout performs more or l..." | Read more » over 9 years ago
WhiteRabbit "Interestingly enough, I did just now find this $889 turf grass color meter which does, indeed, use NDVI! http://www.specmeters.com/nutrient-manage..." | Read more » over 9 years ago
WhiteRabbit "Thanks for the links. Supposedly grass also changes color as the soil loses moisture (IIRC, it becomes less green and more blueish?), and people c..." | Read more » over 9 years ago
warren "I think a lot of the challenge of using an Infragram camera well is the need for comparison. Comparing an area treated in one way with a "control" ..." | Read more » over 9 years ago
warren "Tagging this as an "event" and adding a date tag! " | Read more » almost 10 years ago
warren "Hi Stevie! Just sharing this poster I designed: https://docs.google.com/drawings/d/1gjkbcTxxd6vJYDvFeo7d2_FMi1CFzk-Qqf_De6QWsH4/edit " | Read more » almost 10 years ago
straylight "good work amy, I like the thinking. I've had the optic fibre tactic on the backburner now for a while, I have the fibre, just need to work on a le..." | Read more » almost 10 years ago
warren "If you look at some of Chris Fastie's work on the Infragram technique, he's posted a lot about theater gels as a way to filter certain wavelengths ..." | Read more » almost 10 years ago
mathew "hmmm... neat idea. Some paints have aniline dyes, but many higher quality paints have just pure mineral pigments. the spectrum of the reflectivit..." | Read more » almost 10 years ago
stoft "So, the translucent paint would provide a filter and you'd select the paint color to select the spectral wavelength to detect? ...which is similar ..." | Read more » almost 10 years ago
stevie "Ohh I understand. Ok I might get this wrong (I'm still new to the science) but we were using the mineral oil as a sort of base sample. We know how ..." | Read more » almost 10 years ago
amysoyka "The purpose of the paint is to act as a filter so that only the exact colour wavelength that matched the colour will be absorbed and trigger the li..." | Read more » almost 10 years ago
stevie "Interesting.. with the oil testing kit we've been using mineral oil. Might that serve a similar function? " | Read more » almost 10 years ago