What size or sizes of collam slits do you prefer to work with? Why?
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In the balance between accurate spectra and light sensitivity, the .09mm slit seems to be the best. Its spectral peaks were just as pointy and clear as at .03mm but it produced brighter spectra, without the cutoff and internal reflections that began to be an issue at .12mm.
I believe this is the 2016 full PDF we printed from -- i did a new layout more recently that was just for one size, but this is the full-sized sheet: