| 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 | |||
| warren | "@warren awards a barnstar to Claytonb for their awesome contribution! " | Read more » | almost 6 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 | |||
| suman | "Dear Warren, I am currently looking some literatures on Image Vignetting Correction. I will definately post back after i come ..." | Read more » | almost 7 years ago | |||
| warren | "Ah, i've just learned that I didn't know the definition of vignetting. But I do now -- apologies for mixing this up! I haven't heard anything about..." | Read more » | almost 7 years ago | |||
| suman | "Dear Warren, I checked about the lens vignetting correction under the tag Lens-distortion as you mentioned. However, i didn't ..." | Read more » | almost 7 years ago | |||
| suman | "Thanks for your prompt response warren.....highly appreciable.... Cheers " | Read more » | almost 7 years ago | |||
| suman | "Thanks for your prompt response warren.....highly appreciable.... Cheers " | Read more » | almost 7 years ago | |||
| warren | "There are a few different approaches to this too, but one which definitely works is documented alongside an in-progress web-based approach, both un..." | Read more » | almost 7 years ago | |||
| suman | "Thanks for your response warren and Chris...I highly appreciate it..I was also interested to know about the vignetting effect and how public labs i..." | Read more » | almost 7 years ago | |||
| cfastie | "Do you think i need the targets of known spectral reflectivity in the same bands that will be used to compute NDVI or it can be tested with any mat..." | Read more » | almost 7 years ago | |||
| warren | "Hi -- well, there may be methods like that; just to put in another idea, although you probably won't want to do it; Dorn Cox from Farm Hack has act..." | Read more » | almost 7 years ago | |||
| suman | "Some initial results using your white balance settings are impressive, however in this particular picture the roof of the house is showing high pho..." | 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 |