| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| cfastie | "People post to facebook to get feedback. Facebook posts are not generally intended to help others. Editing a Public Lab wiki does not typically lea..." | 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 | |||
| 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 | |||
| 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 | |||
| cfastie | "The only filter I tried that worked was Wratten 25A. Two blue filters worked poorly. @mathew has tried Rosco #19 which seems to work well. I don't ..." | 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 | |||
| cfastie | "That is correct that a red filter seems to work much better than a blue filter in a Mobius. The conversion Jeff cited is just for removing the IR b..." | Read more » | over 10 years ago | |||
| cfastie | "Apparently Onset manufactures HOBOs to be NIST traceable, but they charge more money for units that pass a calibration test. Jeremy buys the less e..." | Read more » | over 10 years ago | |||
| cfastie | "Bryan, maybe this is what you remember. We deployed a bunch of these in the tundra 15 years ago: . They don't seem that rugged to me. I wonder if..." | Read more » | over 10 years ago | |||
| cfastie | "That looks like a good arrangement. The DVD grating might have to be rotated. The circular grooves in the DVD (concentric to the outer edge) should..." | Read more » | over 10 years ago | |||
| cfastie | "That's good to know that structure from motion works with wide angle photos. It sounds like you have to correct the distortion first. It doesn't se..." | Read more » | over 10 years ago | |||
| cfastie | "That is an excellent Mobius photo. The Mobius is so lightweight that there is no reason not to include one on every flight. The lens is very wide, ..." | Read more » | over 10 years ago | |||
| cfastie | "I'm not sure what the problem is with that Picavet model. It was designed in Sketchup, and it is scaled correctly in Sketchup, so it is 22 cm long...." | Read more » | over 10 years ago | |||
| cfastie | "Great report. The mini bottle and 3D printed Picavet will go in the Public Lab record books. And what a fantastic place to fly. Is that public land..." | Read more » | over 10 years ago | |||
| cfastie | "Those regressions look really encouraging. I guess if I took some photos with my own A2200 and Wratten 25A filter (the same model and filter type y..." | Read more » | over 10 years ago | |||
| cfastie | "The grating (DVD) bends the light as it separates it into colors. So the grating has to be at an angle to the light coming from the entrance slit. ..." | Read more » | over 10 years ago | |||
| cfastie | "Hi Chelsea, I don't have much experience with mobile phone cameras or with mobile phone apps, but I have taken a bunch of repeat photos. An app th..." | Read more » | over 10 years ago | |||
| cfastie | "They sure are. Excel opened the ods file without too much trouble, and the timestamps are right there. I was just curious to look at the data. Don ..." | Read more » | over 10 years ago | |||
| cfastie | "I had a similar experience when I was figuring out how to copy old film negatives. The best (very expensive) scanner at Middlebury College made a b..." | Read more » | over 10 years ago | |||
| cfastie | "Oh right, Picasa. Picasa was once my primary photo organizer. Then Google started to link it up with Google+ so it became a front end to storing yo..." | Read more » | over 10 years ago | |||
| cfastie | "I couldn't get Excel to parse the time stamps either. I averaged every 60 particle counts, so I assume I got a number for every minute. Here is a g..." | Read more » | over 10 years ago | |||
| cfastie | "This is a really important topic. Scott, what is the program in the main image above? Is that what you use to do the sorting you describe here? Wha..." | Read more » | over 10 years ago | |||
| cfastie | "It's often quite easy to access the IR block filter on this type of little camera. In this case you might have to also dismantle the UAV just to ge..." | Read more » | over 10 years ago | |||
| cfastie | "That last setting in the video looks like it might be getting useful. I think the photos will still have more overlap than they need, so you could ..." | Read more » | over 10 years ago |