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I quickly went through the article and saw it's based on Hamamatsu C12880MA chip for actual spectroscopy. According to the datasheet, the resolution is limited to 12-15 nm so the largest difference would be there. It's difficult to judge on radiometric aspects without a detailed (and carefully perfo...

Hello Andy,

Not yet unfortunately -- due to health issues mainly :-/ I'm just back today from another 2 weeks at the hospital. Since end of December I can only work part time and am late on schedule.

Although it's a bit noisy we clearly identify isopropanol on your spectrum

What integration time did you use? With long exposures you should get a very clean curve like on the website. If not, it means alignment can be improved.

I recommend the 31S4M indeed

Hi! Thanks for sharing these modifications :) From what I see in the propanol image, it does indeed look that you are getting a good Raman signal! It would be best to have an intensity plot to confirm and analyze the results, in particular the resolution that your laser is offering (a good tip is to...

This goes a bit out of my comfort zone but my understanding of the Raman effect is that it is a generalization of the Rayleigh scattering process by adding a polarization term which depends on the vibration of bonds, resulting in an heterodyne process between the photon frequency and the vibration f...

Yes, adjusting means tuning the degrees of freedom until you get the best image. Here, thanks to the cage system bars, the only degree of freedom is moving the lens back and forth. On the other hand, it looks like you've a missing lens in the setup :-/ you should have two lenses between the slit and...

Very nice pictures! Thanks for sharing

There is already some good news. Generally speaking, the span required for Raman spectroscopy at 532 nm is much smaller than the total spectrum of most calibration sources like neon or even the fluocompact lamp. So it's not an issue if you don't image the complete spectra of these lamps. Here, you'l...

The slit image is of too low quality for any practical work -- clearly the sign that something is wrong. Could you send a picture on how you adjust the position of the lenses? Preferably once they are at their aligned position. As an order of magnitude, the focus range is on the order of 0.02 mm so ...

I updated some of the forum settings; please try again uploading the files it should work now

a view from the top of the spectrometer is also useful for debugging