| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| 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 » | over 10 years ago | |||
| WhiteRabbit | "Here's a write-up that I'm finding quite helpful: http://publiclab.org/notes/nedhorning/11-01-2013/why-a-red-filter-should-work-well-for-ndvi Eyeb..." | Read more » | over 10 years ago | |||
| WhiteRabbit | "Sounds like gel filters would be tricky at best, so I guess ixnay to that. How about this one? http://www.ebay.com/itm/Optical-Interference-Filter..." | Read more » | over 10 years ago | |||
| cfastie | "I have not seen a cheap filter like Rosco that is truly a narrow band pass filter. It might be possible to combine filters to get a fairly narrow t..." | Read more » | over 10 years ago | |||
| WhiteRabbit | "Cool! Awesome post. I suppose it's wishful (and probably foolish) thinking, but given the the low price of a filter swatch book and the seemingly..." | Read more » | over 10 years ago | |||
| cfastie | "A filter switcher is a viable solution, especially for small cameras. Cameras as large as Powershots might require a big, precise device in front o..." | Read more » | over 10 years ago | |||
| WhiteRabbit | "Thanks, Chris, for your thoughtful and very informative post. If I'm reading it right, perhaps using two monochrome cameras, each with the appropr..." | Read more » | over 10 years ago | |||
| cfastie | "It should be possible to distinguish between stressed and non-stressed lawn grass using NDVI. I suspect that the $900 FieldScout performs more or l..." | Read more » | over 10 years ago | |||
| WhiteRabbit | "Interestingly enough, I did just now find this $889 turf grass color meter which does, indeed, use NDVI! http://www.specmeters.com/nutrient-manage..." | Read more » | over 10 years ago | |||
| WhiteRabbit | "Thanks for the links. Supposedly grass also changes color as the soil loses moisture (IIRC, it becomes less green and more blueish?), and people c..." | Read more » | over 10 years ago | |||
| warren | "I think a lot of the challenge of using an Infragram camera well is the need for comparison. Comparing an area treated in one way with a "control" ..." | Read more » | over 10 years ago | |||
| fnok | "Sounds like a great application for NIR imagery. I think you may even benefit by putting your camera back up in the air --> balloon mapping or a..." | Read more » | almost 11 years ago | |||
| warren | "There's been some discussion of blurry images and how to fix this to some degree in the mailing lists: https://groups.google.com/forum/#!searchin/p..." | Read more » | almost 11 years ago | |||
| drkatnz | "Sure, have provided a zip file link with all the source, and posted some pictures into the article itself. Not sure why the focus sucked on the di..." | Read more » | almost 11 years ago | |||
| warren | "Wow, fantastic. Could you share some of the source images, maybe in a zip file, or samples from your sets of the paddock photos? " | Read more » | almost 11 years ago |