| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| warren | "What's a good way to determine this? Would it work to set up a test somewhere there is H2S, alongside a calibrated H2S detection technique and comp..." | Read more » | over 6 years ago | |||
| straylight | "thanks ygzstc, that makes sense. I think that the approximation that relative intensity measured from the scope can be used in place of the log rel..." | Read more » | about 8 years ago | |||
| ygzstc | "Yes the Beer-Lambert Law is based on -log(I/Io) but it's applicable for a single wavelength value. (https://en.wikipedia.org/wiki/Beer%E2%80%93Lamb..." | Read more » | about 8 years ago | |||
| warren | "It's odd -- I see the graphs. Straylight, can you contact web@publiclab.org so we can figure out what's going on there? " | Read more » | about 8 years ago | |||
| straylight | "Thanks for the question. My apologies that all of the graphs appear to have vanished (they have for me). Not sure why, maybe a hosting issue. Anyw..." | Read more » | about 8 years ago | |||
| anjohn12 | "Quick question, I'm trying to do something similar for a school project. Shouldn't the absorbance of the sample be the negative log of the percent ..." | Read more » | about 8 years ago | |||
| msysinfo | "I need to measure oil concentration in a water mixture. Can a SPECTROMETER be used to measure the oil concentration? If it a solute that dissolves ..." | Read more » | over 8 years ago | |||
| straylight | "Good points and I understand how you feel, coming at his from a chemistry teachers viewpoint myself. I guess it depends on what experiments and dem..." | Read more » | about 9 years ago | |||
| srpratt | "I'm new to the cellphone-becomes-a-photospec phenomenon, as I was told about this by a colleague. As an AP Chem teacher, I'm looking for hacks to ..." | Read more » | about 9 years ago | |||
| ichinarayan | "ok thanks so much " | Read more » | over 9 years ago | |||
| straylight | "In spectral workbench, when you are looking at a spectra, there is an option to export and save the data in a variety of formats, including xml and..." | Read more » | over 9 years ago | |||
| ichinarayan | "wow beyond belief. i thought it was complicated listing program. and how do you exported the spectra image into csv form? thanks a lot " | Read more » | over 9 years ago | |||
| straylight | "Thanks for the question ichinarayan, I exported the spectra in csv form into microsoft excel. From there I selected the wavelengths I wanted to st..." | Read more » | over 9 years ago | |||
| ichinarayan | "what software do you use for your analisis program used to generated graph? " | Read more » | over 9 years ago | |||
| warren | "You're right - it's a pretty high baseline. Something like 10%, no? I believe this is noise, but some may be related to infrared reflectivity insid..." | Read more » | over 9 years ago | |||
| ttaylor | "Warren, it's really exciting to see this sort of technology diffusing out of academia. All of your question are interesting, here are a few more th..." | Read more » | over 9 years ago | |||
| amysoyka | "@matthew, I tried that. It drove me crazy, trying to cut the slit's varying distances apart. (Imm, 2mm, 5mm...etc) Also, I found that I kept getti..." | Read more » | over 9 years ago | |||
| mathew | "nice! @amysoyka. We're also thinking about cutting a bunch so they could be switched in and out at known widths. " | Read more » | over 9 years ago | |||
| amysoyka | " " | Read more » | over 9 years ago | |||
| amysoyka | "slidey in, slidey out " | Read more » | over 9 years ago | |||
| amysoyka | "Warren, you might like this... It is a resizeable slit. It works like a zoom/focus on a camera " | Read more » | over 9 years ago | |||
| mathew | "have you tried switching your camera to "macro" mode? I don't remember having any such low-light problems with the smartphone spec. haven't tried ..." | Read more » | almost 10 years ago | |||
| GreenLeaves | "Hi warren, we have a problem. We wanted to edit our picture, but it didn't work, because the photo doesn't appear on the screen... " | Read more » | almost 10 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 |