| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| cfastie | "Mathew, I haven't seen any spectral data for Rosco paints. Is there any reason to think that they would be better than other paints for NDVI calibr..." | Read more » | about 8 years ago | |||
| mathew | "well, B&H will sell it to you by the gallon. pricey to try out. $42-95 a gallon, but it sure will make a lot of targets. I tried to get chip..." | Read more » | about 8 years ago | |||
| LaPa | "ok, THANKS all of you for the answers. I like that my research note elicits answers that can also affect other. I am interested to make experiences..." | Read more » | about 8 years ago | |||
| cfastie | "It would be great to have a few paints that: had reflectance spectra for 400 nm to 1000 nm, were exterior paint, were matte finish paint, were av..." | Read more » | about 8 years ago | |||
| mathew | "I haven't played around with it, but I'd assume a neutral gray "TV White" and "TV black" paint like these for TV camera calibration would be the be..." | Read more » | about 8 years ago | |||
| cfastie | "I don't know of any commercially available inexpensive calibration targets. A good calibration target will have the same reflectance for all wavele..." | Read more » | about 8 years ago | |||
| LaPa | "Hi, 1) unluckily I don't have access to a spectrometer 2) wich are the companies where I can buy a cheap Calibration targets? 3) may it be fine to ..." | Read more » | about 8 years ago | |||
| LaPa | "Thank you Chris, I'm going to read with the attention the Ned Horning's note that you link! Have a good day! LaPa " | Read more » | about 8 years ago | |||
| cfastie | "Sorry I missed some questions. Calibration targets work outside or in a greenhouse. Calibration targets are hard to find and very expensive. But ..." | Read more » | about 8 years ago | |||
| LaPa | "Hi, could it be a good idea to choose as calibration target the bare soil area that is in each (thousands) photos? Best regards LaPa " | Read more » | about 8 years ago | |||
| LaPa | "1) Could be a good idea put the calibration targets of known spectral reflectivity in Greenhouse to include in the photos ? 2) Where can I get the..." | Read more » | about 8 years ago | |||
| cfastie | "NDVI is based solely on color (near infrared is one of the colors). If a camera records different colors for two leaves, the NDVI computed for tho..." | Read more » | about 8 years ago | |||
| LaPa | "Thank a lot all of you for the consideration and the suggestions! Chris, sincerely I didn't understand from your reply if you consider my directio..." | Read more » | about 8 years ago | |||
| liz | "Hi @LaPa, great to see your note! I'm tagging some other raspberry pi developers @rjstatic and @seankmcginnis " | Read more » | about 8 years ago | |||
| cfastie | "Hi LaPa, Your time-lapse videos are impressive. These are excellent teaching videos. You can clearly see that the NDVI values for the foliage of t..." | Read more » | about 8 years ago | |||
| cversek | "@tobi_k Hi, I am glad that there are others testing out these sensors with a skeptical attitude. Very often, the abosulute baseline readings from ..." | Read more » | about 9 years ago | |||
| tobi_k | "Hey, I also got myself the SainSmart MH-Z14 and I must say, I am not sure if I really trust the values. Mine (using Arduino and the UART interface)..." | Read more » | about 9 years ago | |||
| jefffalk | "Thanks for making the effort to explain and for doing the experiment. Yes, there is an interval of high correlation. " | Read more » | over 9 years ago | |||
| cversek | "@jefffalk Well, I hadn't done any correlation analysis yet, but I tend not to trust algorithms that yield a single number value judgement. To bet..." | Read more » | over 9 years ago | |||
| jefffalk | "Please explain what is meant by: "During the period when I am sleeping peacefully in my tent (after ~25 mins), the RH and CO2 readings seem to fluc..." | Read more » | over 9 years ago | |||
| cversek | "@donblair Yes, it wouldn't be so bad to set up a tent in one's domicile for the purpose of science. It seems like a lot of correlations can be ma..." | Read more » | over 9 years ago | |||
| mathew | "I'm trying to imagine how to calibrate the CO2 sensor-- Do you think we could fill up a series standard-sized balloons of some sort with a known ai..." | Read more » | over 9 years ago | |||
| donblair | "This is fantastic! I love the idea of using CO2 and/or RH as a metric for sleep quality / breathing patterns. I suppose you're getting a much st..." | Read more » | over 9 years ago | |||
| liz | "Hey Green Youth, I just stumbled upon this note, how excellent! How's your work in Vietnam going? Have you tried anything with infrared imagery? Wh..." | Read more » | over 9 years ago |