Public Lab Wiki documentation

Spectral Workbench may be used offline once it is loaded in your browser. To do so, visit:

https://spectralworkbench.org/capture/offline

Once you've visited the above address, you will be able to access that page even without an internet connection, as long as you use the same browser. This should also work on smartphones.

Not all features will be available in Offline mode, since some rely on an internet connection to retrieve relevant data. But you'll be able to save your spectra as images and upload them later if you need.

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Updating

To update your offline site, you must reconnect to the internet and visit the above address. Wait for 30 seconds and you should be prompted to load a new version by refreshing the page.

How it works

Spectral Workbench's Offline mode uses HTML5's offline manifest feature to store a copy of a portion of the Live Capture interface in your browsers's cache.

The offline version is no longer in active development, pending an offline-cacheable version of the website and a possible offline-runnable version using Bitnami or another solution. Stay tuned on the plots-spectrometry list to hear updates.

Instead, try the web-based SpectralWorkbench.org application

• Download the program here: https://github.com/jywarren/spectral-workbench

Launching the application

Once you have downloaded the software, you should be able to open the "application.macosx" folder and double click spectral_workbench.

Mac: First you will be prompted to select a camera. Choose the webcam associated with your spectrometer, which may be "Creative Webcam Live ..." if you bought the video spectrometer kit. Select "None" under Compression.

Linux: Linux users may experience trouble if they do not have a built-in webcam; if you are comfortable coding you can change the line "new Video(x,x,x,1);" to "new Video(x,x,x,0);" which will select the first camera, not the second one.

Windows Installation Instructions

These instructions assume that you will be installing Java, QuickTime and WinVDIG (see below) in the default locations. If you install them somewhere else, then be sure to change the file locations as required.

Install Apple QuickTime

• Go to Apple's QuickTime page and follow the instructions from there.
• You can use the default settings during installation.

Move QuickTime for Java

• There should be a file called 'QTJava.zip' at C:\Program Files (x86)\QuickTime\QTSystem\
• Copy the file to C:\Program Files (x86)\Java\jre6\lib\ext\
• The file might already be there. If so, there's no need to copy it again.

Install WinVDIG

• Download WinVDIG Version 1.01 (note that only version 1.01 works, not newer versions)
• Save the file and run it. You can accept all the defaults during installation.
• After it's installed and you click 'Finish', a window should open called 'QTCap' and it will show you a black box or your webcam stream, if it's plugged in.
• If you don't see your webcame stream, then choose 'Monitor' from the menu, then 'Video Settings'.
• Change the drop-down box to 'Source' and choose your webcam from the list.
• On the right-hand side, change the dropdown box labelled 'Preview' from 'None' to 'Compressed'.
• You should see your webcam feed displayed in the box.
• Click 'OK'.
• Close the QTCap window.

Run Spectral Workbench

• Go to the folder in which you unzipped Spectral Workbench
• From there, change to the folder called \spectrometry_kit\application.windows
• Run spectrometry_kit.exe

You should see a grey screen and the QTCap window again

• Click 'None' from the 'Compression Type' drop-down box.
• Click 'OK'.
• In a few seconds, spectral workbench should start analysing your webcam data.

The above instructions were transcribed from these instructions. You might find more information there if your installation still doesn't work!

Basics

The software has 3 "modes" -- Setup, Analyze, and Heatmap. Setup lets you properly configure your spectrometer before using it. Analyze is the main mode you'll be using when testing samples. Heatmap uses a color gradient to display finer differences in your spectra, and is otherwise the same as Analyze.

Setup

Click the "Setup" tab at the top. You will see a small "preview" window indicating the height of the sampling row. You can drag to select the area you'd like to sample from, which will be averaged to produce your spectral data.

This is a chance to adjust the amount of light you're using as your source. If you have a dimmer, turn the dial until the red, green, and blue intensity curves are full height, but not "hitting the ceiling" -- which would mean you were losing data due to overexposure.

(see plans for improvement)

Store a baseline reading

Now that your spectrometer is set up correctly, you can store a "baseline" reading of just your sample container with no sample material. Place your sample container between the light and your spectrometer and press the spacebar. The spectrum you were seeing should be "saved" as a red line which persists even if you remove the sample container.

Measuring a sample

Now place the sample in its container in front of the spectrometer. You should see the white line drop below the red line - this is because your sample is absorbing some of the light. A new, yellow line will appear, representing the amount of absorption.

Saving a spectrum

Before saving, name your spectra by typing a name. It will appear in the top bar. Press "Save" and the SpectralWorkbench.org website will open in a window and prompt you to log in and save your data.

For some, the "Save" function is not working properly, and although the data is uploaded, it is not attached to your account. To get around this, you can open the "spectra" folder which you will find in the same folder as your application. There you will find any spectra which you have saved, which you can upload directly at SpectralWorkbench.org. (read about this bug here)

Software issues:

Linux app wont boot - this may be due to the absence of the GSVideo library. Copy the folder called "libraries" from your /spectral_workbench/ directory into your Processing "sketchbook". It should contain the GSVideo library and the ControlP5 library. Now restart Processing or reopen the app.

In your request, consider:

• Did you launch the platform-specific version in the Mac OS X or Windows folders, or run it from within Processing (http://processing.org)?
  • If you're having trouble, please try the Processing version, as it generates more useful error output.
• If you run it in Processing (processing.org) can you copy and paste the debug output from the Processing window and post/send it? That's much easier to diagnose.
• Do you have a webcam and does it work normally in Photo Booth (mac), Cheese (linux), VLC (windows and linux) or whatever webcam app Windows has?
  • Did you close other webcam-using applications and free up your webcam before launching Spectral Workbench?

Mac OS X

• What version of Mac OS X are you using?
• If you see a grey screen, does a your webcam light up for a moment? There is a bug where a popup window asks you to choose a camera, but it can't come to the front because the app is fullscreen. You might try apple-tab once you see the green light come on.