| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| DarylWM | "Thanks for sharing your work. I've had the same trouble trying to find the spectral response curve for the OV5647 sensor, so this technique was ver..." | Read more » | about 9 years ago | |||
| pswigert | "Hi! I really enjoyed this thread and seeing everyone's thoughts and responses to the question. @WhiteRabbit , I was wondering if you have any updat..." | Read more » | about 9 years ago | |||
| WhiteRabbit | "I found this: http://www.vernier.com/products/sensors/col-bta/ which is interesting because unlike other low-cost spectrometers/colorimeters its s..." | Read more » | over 9 years ago | |||
| warren | "Wow chris the barcode scanner filter idea is great!!! " | Read more » | over 9 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 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 » | almost 10 years ago |