| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| stoft | "Light is a wave, but think about it as particles. The 'beam' of light is aligned within a relatively narrow angle between a slit and the diffractio..." | Read more » | over 9 years ago | |||
| stoft | "Liz, good points. It might be useful to draw a general dividing line between research and data collection. Research often requires data collection,..." | Read more » | over 9 years ago | |||
| stoft | "This is a good topic and, IMHO, points to the heart of entire PLab hypothesis -- that reproducible scientific measurements are possible by a broad ..." | Read more » | over 9 years ago | |||
| stoft | "Yes, this is a good topic. I did some work on this; maybe it will help. First, the 'size' of the spectrometer (the PLab type) is mostly decided by..." | Read more » | over 9 years ago | |||
| stoft | "They look good in the pic. It is difficult to get a ideal gradients with actual dots or lines. You might try attenuating the florescence light vs l..." | Read more » | over 9 years ago | |||
| stoft | "btbonval - point taken, centriod is for 2D; their line just represents the 'center of distribution' " | Read more » | over 9 years ago | |||
| stoft | "btbonval - true. I was just suggesting a fast integer approximation as a simple means to test and get a 1-number result. The existing work in patte..." | Read more » | over 9 years ago | |||
| stoft | "I think the term you are looking for is the "centroid" -- think of it as the point where the shape/volume/whatever would be physically balanced -- ..." | Read more » | over 9 years ago | |||
| stoft | "Looks promising. Maybe these are obvious but... - Pick 3-5 oils, or oil mixtures, as a reference test set -- low to high density -- then use them f..." | Read more » | over 9 years ago | |||
| stoft | "Clever. Not sure where you intend to take this experiment, but grab-n-drag the photo and having a semi-transparent mode (to see the map below the p..." | Read more » | over 9 years ago | |||
| stoft | "Good observations -- but why use a CFL which has poor SNR for wide-band averaging because the spikes prevent using higher light intensities for bro..." | Read more » | over 9 years ago | |||
| stoft | "Jeff, Yes, you could double the slit width and double the exposure but you also significantly decrease the resolution. That said, I've noticed that..." | Read more » | almost 10 years ago | |||
| stoft | "So, the translucent paint would provide a filter and you'd select the paint color to select the spectral wavelength to detect? ...which is similar ..." | Read more » | almost 10 years ago | |||
| stoft | "Ok, so the plots are absorption; which makes more sense. However, the Y axis is labeled "Intensity". It would be more clear to either plot relative..." | Read more » | almost 10 years ago | |||
| stoft | "Nice experiment. As I recall, white LEDs have a significant 'bump' at about 430nm, a dip at 470nm and a broad peak about 600nm so I assume the 470 ..." | Read more » | almost 10 years ago | |||
| stoft | "Jeff, I constructed a few more slotted filters which just bend a bit and fit in front of the smartphone slit. The camera focus difficulty limits th..." | Read more » | about 10 years ago | |||
| stoft | "Yes, true. No slight intended. I edited my comment to note that 'broken' means only that the disconnect between the app and Chrome Beta is still th..." | Read more » | about 10 years ago | |||
| stoft | "(original comment seems gone...) ...I commented that I did try a pattern but that the auto-focus for the default camera appeared to focus momentari..." | Read more » | about 10 years ago | |||
| stoft | "Ok, guess having the exposure default to max isn't too bad, but actually setting the exposure to max is better. I've seen evidence that the standar..." | Read more » | about 10 years ago | |||
| stoft | "Depends on what you want to monitor. If the whole spectrum is dynamically changing, then maybe not because the relationship between clipped peaks a..." | Read more » | about 10 years ago | |||
| stoft | "Jeff, re: "...scale to live capture...". I'll have to guess that you mean observing spectral responses over time with the idea of generating a 'wat..." | Read more » | about 10 years ago | |||
| stoft | "Great; the paper should help. Now move the lamp about 4 ft away.... the bands should no longer look saturated. A couple other thoughts. I've not u..." | Read more » | about 10 years ago | |||
| stoft | "Congratulations on your assembly. However, the photos above suggest a misunderstanding about using the device. Remember, there is a 'slit' through ..." | Read more » | about 10 years ago | |||
| stoft | "Sreyanth, Jeff, I may not be up on the latest strategy for the code projects, but I'm still sensing that some concepts are diffuse. Performing fre..." | Read more » | about 10 years ago |