Welcome! This page includes full instructions to assembling the Public Lab Desktop Spectrometry Kit.

Preorder one from our store (shipping Feb 2013)

This page is being actively improved, so be sure to check back soon to see if more content has been added.

Getting Started

The 1-page instruction sheet which shipped with your spectrometer remains the best documentation to date on how to assemble it. Download a new copy here:

desktop-kit-instructions-0.2.pdf (100 kB)

Using your spectrometer

Once you've assembled your spectrometer and are ready to use it, plug it in and visit SpectralWorkbench.org to begin recording data with it. The web-based software works in the Chrome and Opera browsers with more coming soon.

(Peer) Support

Public Lab is not a corporation, we're an open community of DIY environmental science researchers which you have just joined! The best place to get help is the spectrometry mailing list; to join, register on this site and be sure to check the "plots-spectrometry" box.

The spectrometry mailing list is made up of people like you, who are building and improving open source spectrometry techniques. Ask questions, look for help, and consider helping others too!

Resources

• more Assembly instructions
• Using the software
• Background about the project
• peer-contributed research on open source spectrometry

Assembly photos

...coming soon! (under construction)

4. Snap off the useless half of the webcam

Some cameras may sit flat on the bottom of the box; our kit includes a nice, compact camera with flat sides (hard to find! too much ergonomics!) but you can make it even smaller by snapping it in half.

If you can't find a flat-bottomed camera, you can use hot glue, epoxy, moldable plastic, or metal brackets to ensure that your camera stays level and rigidly in place.

6. Split the DVD-R into layers and cut a small rectangle from the clear layer

Don't get fingerprints on the DVD, and cut your "grating" from the outside edge where the track lines are more parallel. You can cut this piece down more precisely later.

7. Apply gentle pressure with pliers to open the webcam, and cut the DVD to fit inside the lens hole

You'll have enough DVD to try again if this goes wrong. Align the outside edge of the DVD so the track lines will appear vertical in the resulting video.

8. Tape or glue the DVD piece in place

Superglue may leave a "frosty" looking stain, so try hot glue or epoxy. Tape works fine -- just don't cover where the camera will look through.

9. Unscrew the lens and remove the infrared filter

Heating the lens a bit with a hair dryer can help loosen it. The filter will look iridescent -- you can throw it away. Screw the lens back in close to how it was.

More tips on removing filters from other types of webcams can be found here: Webcam filter removal

10. Look at a barcode through the webcam to refocus it to about 20 cm (8") away

Use a webcam program like Photo Booth or even https://spectralworkbench.org/capture (experimental). A barcode has fine details so it's a nice test of focus. (The above image is of an older kit)

Rotate the camera lens to adjust the focus. You may need to gently use a pair of needle-nosed pliers at first. Anything around 8 inches away from the lens should be in focus. This means your slit will be in focus when the box is closed. If you don't carefully refocus your camera, your spectra will be of very low resolution.

Now snap your webcam back together.