Comments

Author Comment Last activity Moderation
cfastie "The first two times I tried the Rev. P wind sensor, I also tried the Rev. C sensor. The Rev. C sensor did not work as well as the Rev. P, so I focu..." | Read more » almost 4 years ago
cfastie "It’s fairly straightforward to use the Modern Device Wind Sensors with either a Mini Pearl Logger or a Nano Data Logger. I had great success with t..." | Read more » almost 4 years ago
cfastie "Sodium lamps have very distinctive spectral emissions, so it is fairly easy to distinguish them from other types of lamps. Once you become familiar..." | Read more » almost 4 years ago
cfastie "I have tried several times to adjust the histogram of bad infrared photos. It has always failed and I don't know why. I assume it is because the ad..." | Read more » almost 4 years ago
cfastie "A single camera NDVI system with a red filter should produce a photo with very turquoise foliage. The blue channel (NIR) should be much brighter th..." | Read more » almost 4 years ago
cfastie "I have not used graphing for live debugging because I didn't know how easy it was to do. I use the live serial monitor in the Arduino IDE all the t..." | Read more » almost 4 years ago
cfastie "This is a terrific result for one of your first flights. The photography is very high quality because of the good decisions you made. If this is yo..." | Read more » almost 4 years ago
cfastie "I know nothing about this topic, but here is the model I concocted from whole cloth to understand it. Measuring conductivity of water with electro..." | Read more » almost 4 years ago
cfastie "This is a great trick. I have made a bunch of these. If you are doing this with a cheap USB cable, you might want to check the red and black wires ..." | Read more » almost 4 years ago
cfastie "There is also lots of good information in this research note by Don about some testing he did. " | Read more » almost 4 years ago
cfastie "There has been a lot of information about measuring turbidity posted at Public Lab. Don Blair posted an excellent review of the common approaches t..." | Read more » almost 4 years ago
cfastie "Kestrel makes a well-thought-out data logger called Kestrel Drop. The Drop D2 logs temperature and humidity apparently for six months. You can retr..." | Read more » almost 4 years ago
cfastie "Spectrometers based on consumer cameras, like the Public Lab spectrometers, can be built so they provide good information about which narrow wavele..." | Read more » almost 4 years ago
cfastie "First, mark the position of the three screws. When you remove them, count the number of rotations needed to unscrew them. So you will need marks on..." | Read more » almost 4 years ago
cfastie "The rules for flying drones are different from the rules for flying kites or balloons. The rule that flying is prohibited within five miles of an a..." | Read more » almost 4 years ago
cfastie "The Public Lab desktop spectrometer is quite capable of making a spectral graph of sunlight reflected from grass. The curve will differ from the pr..." | Read more » about 4 years ago
cfastie "An infragram photo file does not contain enough information to produce a normal color image of the scene. The infragram filter blocks most of the b..." | Read more » about 4 years ago
cfastie "So, the values in the graph are computed as follows? The values from the camera for each channel (R, G, B) range from 0 (no light) to 255 (maximum..." | Read more » about 4 years ago
cfastie "The signature of ripe coconuts might be distinguishable from some of the other things in the photos, but not necessarily everything else in the pho..." | Read more » about 4 years ago
cfastie "I don't know of published results of studies comparing red and blue filters. Red light has been used for the visible part of the NDVI equation for ..." | Read more » about 4 years ago
cfastie "Computing NDVI requires a value for the "brightness" of both red light and near infrared light for the same part of a scene (or for each pixel). Un..." | Read more » about 4 years ago
cfastie "Yes, I agree that this is a different approach to an issue that has had a lot of effort directed at software solutions. This is a purely hardware s..." | Read more » about 4 years ago
cfastie "Hi Adam, Those thermoelectric fans are very smart. This guy on YouTube shows how to make one with a $3.00 thermoelectric module and parts recycled..." | Read more » about 4 years ago
cfastie "Oh, you're right. The older lut used in the images above can be found here: https://publiclab.org/wiki/photo-monitoring-plugin " | Read more » about 4 years ago