Spectrometry
question: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 "Yes definitely the diy spectrometers on this site can have their range narrowly selected. See SpectralWorkbench.org for some examples! " | Read more » about 6 years ago
Aleksi12358 "So it is possible to use spectrometer as colorimeter. Is it possible to choose to read narrow band of spectrum with Public lab spectrometer softwa..." | Read more » about 6 years ago
Pushpaw "Just tried it and it is important to note that what you will see is 3 dots once the laser beam has passed through the diffraction grating. One is w..." | Read more » about 6 years ago
Tomas0413 "The grating orientation might be the thing. I somehow didn't think about it before. I do have a laser pointer, and when I tried a few weeks ago, I ..." | Read more » about 6 years ago
Pushpaw "As far as I can see that camera placement looks as it should. Going off on something of a tangent, do you happen to have a laser pointer. If you po..." | Read more » about 6 years ago
Aleksi12358 "Thank you for links. I will contact person who designed that automatic water tester and ask few question about accuracy of readings and use of diff..." | Read more » about 6 years ago
Tomas0413 "Thanks for prompt replies. I'm travelling now without access to the spectrometer, I'll share new photos on Mon/Tue next week. " | Read more » about 6 years ago
Aleksi12358 "Thank you for suggestion. I will look into it. " | Read more » about 6 years ago
warren "I would try with the DVD first just because it's easier to know when it's properly aligned. Then upon confirming nothing else is wrong, and it's wo..." | Read more » about 6 years ago
warren "OK - that's OK, the camera should be looking at the dark inside surface of the lid. The grating or DVD should bend/refract the light downward into ..." | Read more » about 6 years ago
Tomas0413 "Warren, for now, I just completely removed the grating. And actually, I no longer use a slice of DVD, I bought a set of gratings (an upgrade). When..." | Read more » about 6 years ago
Tomas0413 " " | Read more » about 6 years ago
Tomas0413 "Pushpaw, thanks for the reply. Not sure why you mention auto-focus, you don't want it, and I'm pretty sure the camera that ships with the spectro..." | Read more » about 6 years ago
warren "Also Markos, from the spectrometry mailing list, chimed in with:grinning: Hi, I apologize for sending here a reply to the question proposed at: ..." | Read more » about 6 years ago
Ag8n "The public lab instrument will cover a part of the NIR. Unless you can find very cheap used FTIR, the cost of the instrument will far exceed your ..." | Read more » about 6 years ago
warren "And in case there are updates from others, let's see if @Frikkie or @winsorje have something to add? " | Read more » about 6 years ago
warren "Maybe @fez who asked this would be interested too: https://publiclab.org/questions/fez/02-01-2017/diy-methods-for-nitrate-detection-in-food " | Read more » about 6 years ago
warren "Hi, just for starters there are a couple interesting projects related to nitrate detection here: https://publiclab.org/tag/nitrate There's also t..." | Read more » about 6 years ago
Ag8n "I have very little experience with soil testing. So the local extension agent was called. He suggested the lamotte NPK test kits. One that will ..." | Read more » about 6 years ago
Aleksi12358 "Hello. I would like to measure every plant nutrient from macro to micro but I think macro nutrients(nitrogen, potassium, phosphorus, sulfur, calci..." | Read more » about 6 years ago
warren "Hi, which nutrients are you hoping to measure? " | Read more » about 6 years ago
Pushpaw "Your Guvcview control panel looks much like mine running on a real Ubuntu PC (If I understand you correctly you are running it in a virtual machine..." | Read more » about 6 years ago
Tomas0413 "And this example says FixedFocus: Look what I found on AliExpress http://s.aliexpress.com/yiIBvmiy " | Read more » about 6 years ago
warren "Great, i look forward to seeing the photos. Please also upload one of the front slit of your box! I don't think autofocus would cause complete dar..." | Read more » about 6 years ago