| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| cfastie | "Hi LaPa, Your time-lapse videos are impressive. These are excellent teaching videos. You can clearly see that the NDVI values for the foliage of t..." | Read more » | over 8 years ago | |||
| cfastie | "Yes, those photos are good. Ideal photos have some live plants, maybe some recently dead leaves, and some things that are not foliage. Outdoor phot..." | Read more » | over 9 years ago | |||
| warren | "Specifically, I think we need to encourage people to structure experiments around what these cameras do best at the moment -- comparisons between v..." | Read more » | over 9 years ago | |||
| cfastie | "I think you're right that subjective is the wrong word. Maybe qualitative. A plant with an actual NDVI value of 0.5 may have an infragram NDVI valu..." | Read more » | over 9 years ago | |||
| warren | "Hi, Chris - I've been plugged into several other projects and really didn't have time to do this properly, and there was some confusion over the we..." | Read more » | over 9 years ago | |||
| cfastie | "A standard coefficient is a tough nut. The amount you would want to shift the NDVI values will differ a lot among photos. Exposure and color balanc..." | Read more » | over 9 years ago | |||
| warren | "It looks to me like both offer pretty good differentiation, but that the red filtered version depresses NDVI values. But since we're not assuming a..." | Read more » | over 9 years ago | |||
| warren | "You're right - we need to display the colormap in the saved images too -- but we haven't had any time to do further development on Infragram.org, s..." | Read more » | over 9 years ago | |||
| warren | "The colormap is based on one of yours: " | Read more » | over 9 years ago | |||
| cfastie | "Yes, I can't say much without seeing the originals. Someone familiar with what infragram.org does might be able to infer something. When I follow ..." | Read more » | over 9 years ago | |||
| warren | "Do you think there's nothing you can infer without the originals? I'm guessing you want to look at the blue/red gap? These are the camera serial n..." | Read more » | over 9 years ago | |||
| warren | "I think they're gone, honestly. The bug seems to affect images captured via the webcam direct connection, but not images which were uploaded. I don..." | Read more » | over 9 years ago | |||
| cfastie | "Can you attach the original photos from the camera? Or do they exist only locked in the burly depths of Infragram for eternity? " | Read more » | over 9 years ago | |||
| warren | "These are all NDVI except the third, normal looking one which I labelled "original". Unfortunately a bug in infragram is not allowing display of th..." | Read more » | over 9 years ago | |||
| cfastie | "I'm confused about which images are photos from the camera and which are NDVI images. It would also help to know what the colors mean in NDVI images. " | Read more » | over 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 » | almost 10 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 10 years ago | |||
| warren | "Wow chris the barcode scanner filter idea is great!!! " | Read more » | over 10 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 » | 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 |