Comments

Author Comment Last activity Moderation
cfastie "What should I do to this pictures to improve the NDVI calculation? There is not much that can be done after the photo is taken to improve its abil..." | Read more » 30 minutes ago
cfastie "It is likely that the library that you do not want to use will provide the functionality that you are seeking. Adding these lines (and installing ..." | Read more » 2 days ago
cfastie "Brendan, That's good news. A Rosco 2007 filter was somehow attached to the lens of the RPi camera. That filter passes blue and NIR light but not mu..." | Read more » 13 days ago
cfastie "This is a great question. I don’t have much information about how these photos were made, but I will make some assumptions. I assume the Pi NoIR ca..." | Read more » 13 days ago
cfastie "If photos are taken of plants in two treatments (top and bottom) with the same camera settings (all manual control) under the exact same lighting c..." | Read more » 3 months ago
cfastie "`>> CCS-811 VOC sensors do not need regular calibration or initial calibration, as they use a different technique and not laser-scattering? ..." | Read more » 3 months ago
cfastie "Here is some new data from a gas sensor. This is a module with a CCS-811 sensor (provides an estimate of total volatile organic compounds [VOC]). T..." | Read more » 3 months ago
cfastie "The Adafruit VOC sensor module uses a CCS-811 VOC sensor. Modules with these sensors cost about half as much when purchased on eBay from sellers in..." | Read more » 3 months ago
cfastie "The Arduino snow depth gauge seems to produce good data. It is an ESP8266 and laser rangefinder I2C sensor ($9 total cost). As expected data collec..." | Read more » 4 months ago
cfastie "The sunlight is not an issue. For a winter-long monitoring goal, a few measurements every day are plenty, and those can be taken at night. With the..." | Read more » 4 months ago
cfastie "I tried one of those little six dollar laser rangefinders (vl53lox) for measuring distance to snow. Those rangefinders don't work at all in sunligh..." | Read more » 4 months ago
cfastie "I think a laser rangefinder might work well for this. Put it on a pole and point it downward to measure the distance from the rangefinder to the sn..." | Read more » 4 months ago
cfastie "Using green foliage (or chlorophyll) to set a custom white balance deserves more consideration than I gave it in my last comment. Foliage absorbs r..." | Read more » 5 months ago
cfastie "The goal of the custom white balance hack is to fool the camera into wildly exaggerating the brightness of the blue channel (when using a red filte..." | Read more » 5 months ago
cfastie "If your K610 filter is a cutoff filter that passes wavelengths greater than 610nm and blocks shorter wavelengths, then it is similar to many filter..." | Read more » 5 months ago
cfastie "`>> for simple bandpass filters, I use the letter "K" followed by the approximate cutoff wavelength Are your filters bandpass filters or cut..." | Read more » 5 months ago
cfastie "I have not heard of anyone using a microcontroller (Arduino or ESP board) to read data from an SD card. But maybe it is possible. A more common str..." | Read more » 5 months ago
cfastie "I haven't tried that Feather combination. I have also never seen a list of Feather-Featherwing combinations that are incompatible. So I assume it w..." | Read more » 5 months ago
cfastie "It looks like the PIC12LF will do what you need. There is also a low power 555 timer (TLC555) but it is not as low power as the PIC12LF. " | Read more » 6 months ago
cfastie "The TPL5110 depends on getting a signal to the DONE pin, so I am not sure it can just send a pulse every eight seconds. The TPL5111 sets an enable ..." | Read more » 6 months ago
cfastie "I think NDVI will provide some information about the photosynthetic rate of mosses. Moss leaves capable of rapid photosynthesis will probably be ab..." | Read more » 7 months ago
cfastie "I'm not familiar with the details, but I think the goal was to protect the sensor from precipitation (the outer can), radiation (the aluminum foil ..." | Read more » 7 months ago
cfastie "`>>Is it possible to use an NIR sensitive camera to take the image and then use the red and the NIR as two separate copies of the same image ..." | Read more » 7 months ago
cfastie "`>>So according to this we should be getting about 10% transmission of red light, does that mean I should subtract 10% of each pixel value in..." | Read more » 8 months ago