Still trying to solve the monitor calibration problem — need to measure the actual spectral output of my monitor's primaries, not just RGB. The CR30 held against the screen gives something, but it's not designed for emissive sources. What I need is the pocket jewel spectroscope I've been using all along, properly …

After successfully reverse engineering the CR30 colorimeter, I found myself wanting something more versatile - a device that could not only measure reflected light but also handle transmittance measurements with fiber optic coupling. The result is this compact, portable visible light spectrometer built around a …