What I want to do

I use the spectrometer as a relative reflectance spectrometer to measure the change in color when a 3d-object is placed in front of a card. The question is how will an object with a different color than a painted surface influence the perception of color. I don't have the time to fully research this, but I will try to measure a difference in the reflected spectrum.

I know now from one of (I think) Warren's notes that the webcam sensor is not capable to measure intensity's accurately. But I hope that by comparing value's I get a relative difference.

I use a matte black paper box and place a strong halogen light source parallel to the old videocassette style spectrometer inside. Both of them face a Matte black cardholder. This holds an A6 sized card. I start with a white colored card and place a smaller colored card near the first.

Instead of images I try to capture the combined values and compare the graphs to find estimate the difference with or without a different colored object in a near region.

My attempt and results

This variable/command will deliver the valuables for R, G, B and the medium or combined value. I'm looking for a way to get online the combined value. Also I have no idea how to get the wavelength value's of the x-axle.

Macro: setup: function() { // code to run on startup $W.mode = "average"
alert($W.full_data) }, draw: function() { // code to run every frame

} end macro

Questions and next steps

How do I get the combined values only? How do I get the average combined values over a small time period?

How do I get the corresponding wavelength values?

Why I'm interested