[PLOTS] SPECTROMETER THOUGHTS

[Adam Griffith]

On an airplane in Europe, I had a great conversation with Dr. G. Tempea, a laser physicist, regarding spectral resolution.

Design ideas:
- could the resolution be increased by using a Blu-Ray DVD as the diffraction grating?
- could the resolution be increased by using a camera with a larger sensor? Higher megapixels?
- what are the CCD limitations?
- could the resolution be increased by increasing the distance between the diffraction grating and the "screen?"

Application idea:
- color calibration for computer monitors. Right now, the software to do color matching (for printing, among other things) is expensive and proprietary.

Adam

--
Adam Griffith
Director of Science and Coastal Environments
publiclaboratory.org
828.321.2326

[Mathew Lippincott]

Adam, that's an awesome idea.  Color calibration is outrageously expensive.  I've done it manually to save money, and I still needed and a calibrated printed color chart($60), and did the work in sunlight.  That's the cheapest option and its pricier than our spectrometer.

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[Adam Griffith]

That's good to hear, Mat.  Do you have any web links for what we are chasing in terms of the technology?  Alternatives, etc?

(I've never cared too much about color, but that probably shows in my wardrobe.)

[Jeffrey Warren]

All your suggestions would probably result in higher spectral resolution, and are worth trying. Giuliano Moschini demonstrated that simply doing more careful and rigid construction and narrowing the slot could result in substantially higher resolution:

http://spectralworkbench.org/sets/show/6

My biggest interest right now is dynamic range, though -- for many samples, the signal is so weak that there's not much data to look at, really. But JoshMC has been having a lot of success reading up to 60% brightness for his UV tests of everything from laundry detergent to Listerine:

http://spectralworkbench.org/spectra/show/236

I really NEED to spend some time refining and tidying up the software a bit. But I really WANT to spend some time centrifuging sediment from the Gowanus Canal and doing UV tests like JoshMC's been trying.

Jeff

[Mathew Lippincott]

Adam, 

its been 4 years since i've done much screen calibration.  at the time, analog systems were being replaced with digital pretty fast.  I can't find any screen calibration chip charts for sale, but here is a camera version. The display calibration versions were similar, only all the greys and colors ran along the border, so that they could be placed on a screen and compared to an on-screen chart.