| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| nstarli | "Where can I find the blue calibration card? I could not find it on the public lab store. " | Read more » | over 4 years ago | |||
| cagiva | "@cfastie, You were absolutely correct. The Blue card from PublicLab arrived today so I redid the white-balancing calibration with it and I got much..." | Read more » | over 5 years ago | |||
| cfastie | "Performing a custom white balance on a blue-filtered NIR camera fools the camera into exaggerating the brightness of the red channel. The red chann..." | Read more » | over 5 years ago | |||
| cfastie | "Sid, Pretty big difficulties. The sensor does not know what hit it. Each pixel produces a value for brightness (for one channel) which depends on ..." | Read more » | almost 7 years ago | |||
| sid | "This is excellent work here! I was wondering how software could help eliminate the tedious task of installing a red/blue filter. If an IR enabled ..." | Read more » | almost 7 years ago | |||
| bwarzak | "I agree with Chris. Narrower bands, when they are optimally centered, logically will work better, particularly because - virtually inherent with in..." | Read more » | about 7 years ago | |||
| cfastie | "Some blue filters including Wratten 47, Schott BG3, and Rosco 2007 are dual bandpass red-rejection filters. They require that blue light be used fo..." | Read more » | about 7 years ago | |||
| suman | "I have just been going through a peer reviewed journal paper named 'Monitoring plant condition and phenology using infrared sensitive consumer grad..." | Read more » | about 7 years ago | |||
| reversevector | "Since these cheap consumer cameras have a lot of NIR crosstalk, especially with small sensor cameras like the GoPro, would it be better to subtract..." | Read more » | about 7 years ago | |||
| nedhorning | "I do not have any peer-reviewed papers related to this work - sorry. Ned " | Read more » | about 7 years ago | |||
| suman | "Dear Ned, Recently i have been going through your interesting works on Infragram NDVI and calibration. I was wondering if you had a..." | Read more » | about 7 years ago | |||
| sujayj | "Thanks Chris " | Read more » | about 7 years ago | |||
| cfastie | "You can use any filter that blocks most blue and green light (all visible light other than red) and also passes a lot of near infrared light (somew..." | Read more » | about 7 years ago | |||
| platteferguson | "So my million dollar question do I buy 3 or 4 inspire 2.0 with extra batteries or go for the new Ebee SQ ag drone for 12-15k with the multi spec wi..." | Read more » | about 7 years ago | |||
| dannysmith | "thanks @Claytonb, they seem like the way to go " | Read more » | about 7 years ago | |||
| Claytonb | "@dannysmith -I have been using the Labsphere Permaflect coated targets http://labsphere.com/labsphere-products-solutions/materials-coatings-2/coati..." | Read more » | about 7 years ago | |||
| dannysmith | "@Claytonb - I was just wondering if you could indicate what type of calibration targets you are using? I've been looking at targets produced by lab..." | Read more » | about 7 years ago | |||
| cfastie | "The spectral response figure came from an article linked in this thread: https://groups.google.com/forum/#!topic/plots-infrared/aJhM30D6bUM That's..." | Read more » | over 7 years ago | |||
| curiousity | "thanks to @cfastie for the interesting charts... How did you take it ? Looking at chart, using just the blue channel as NIR the NIR/VIS sensitivi..." | Read more » | over 7 years ago | |||
| cfastie | "All three Bayer filters (R,G,B) transmit some near IR light. Above: Spectral response of a Canon PowerShot A2200 before (top) and after (bottom)..." | Read more » | over 7 years ago | |||
| curiousity | "You said ...With the red filter we can be fairly confident that the blue channel contains primarily NIR light... But how this happens ? As I know..." | Read more » | over 7 years ago | |||
| Claytonb | "@Artichoke23 - What I have seen in testing is that a red filter will give you much greater contrast and sensitivity in crop vigor. A good example i..." | Read more » | over 7 years ago | |||
| Artichoke23 | "@Claytonb, This is a great post and comparison. I have a couple questions, I'm using the V2 NoIR Raspberry Pi camera and #2007 filter they provide ..." | Read more » | over 7 years ago | |||
| everydayduffy | "Thank you @Claytonb. " | Read more » | almost 8 years ago |