| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| MrBumper | "I'm wondering if you took any account of the web camera settings - in particular colour temperature / white balance. This has quite a large effect ..." | Read more » | over 9 years ago | |||
| mathew | "my experience has been similar-- just because a very bright source in the 800-1000nm range can be detected doesn't mean that we can trust the sensi..." | Read more » | over 9 years ago | |||
| stoft | "Thanks. Yes, the camera has virtually no relative sensitivity outside 400-700nm. This does need to be differentiated from observing a bright source..." | Read more » | over 9 years ago | |||
| mathew | "This is awesome, Dave! The noise above 700 and below 400nm is substantial, but I think that just defines the usable range of the spectrometer. @w..." | Read more » | over 9 years ago | |||
| warren | "Very true, re: alignment -- is there any way to do a tiny tiny amount like a nanodrop while keeping the (possibly toxic) sample material sealed som..." | Read more » | over 10 years ago | |||
| warren | "Well, ideally, much smaller would be great -- i think the ones you've found are mostly 15ml?, but the reality may be that nail polish bottles just ..." | Read more » | over 10 years ago | |||
| mathew | "if we're locking in alignment for the laser, and settling on mineral oil for a solvent, I don't actually think a container-less cuvette is a crazy ..." | Read more » | over 10 years ago | |||
| natalie | "Do any of the samples I have sent thus far match this criteria? " | Read more » | over 10 years ago | |||
| warren | "Maybe -- the paper describes different kinds of filtering, one from when the laser enters the liquid, one from when the fluorescence exits the liqu..." | Read more » | over 10 years ago | |||
| mathew | "Is this why the "microdrop" style is so popular? could we reduce the filtering effect by totally saturating the sample with laser light? " | Read more » | over 10 years ago | |||
| warren | "OK, links to some citations. I'm visiting an MIT building now so it's hard to tell which are open access; i'll try to check on this later: Jiji et..." | Read more » | over 10 years ago | |||
| warren | "Interesting -- specific PAHs are (as we've seen in other literature) out of the 400-1000nm range of our device: monoaromatic compounds (benzene, t..." | Read more » | over 10 years ago | |||
| warren | "p56 mentions "polycyclic aromatic hydrocarbons (PAHs), pesticides, environmental hormones" as contaminants that can be detected with fluorescence s..." | Read more » | over 10 years ago | |||
| warren | "So the Carstea paper is great for one particular reason - we've suspected that organic material could fluoresce and potentially interfere with our ..." | Read more » | over 10 years ago | |||
| warren | "Aha! Line 7 of p54 says: The Raman scatter line can be used to check for instrument stability and to quantify the degree of contamination from a w..." | Read more » | over 10 years ago | |||
| warren | "p.51 has a discussion of pH and salinity on spectra: "intensities increase with higher pH until 10, as observed by Reynolds and Ahmad (1995) at raw..." | Read more » | over 10 years ago | |||
| warren | "Page 50 also discusses filtering effects -- where the color of the sample itself (yellow, brown) can filter out some wavelengths of fluorescence. T..." | Read more » | over 10 years ago | |||
| mathew | "Cool! added it here: http://publiclab.org/wiki/spectrometer-history " | Read more » | over 10 years ago | |||
| warren | "Linked to from http://publiclab.org/wiki/oil-testing-kit#Challenges " | Read more » | over 10 years ago | |||
| warren | "@mathew - just dug up this old note, which shows a method for equalizing area. I'd love to find more literature on the subject, but it's worth a tr..." | Read more » | over 10 years ago |