| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| cfastie | "That's a really clever idea, and I think it might work. However, it assumes that: The photos must be simultaneous if anything in the scene is cha..." | Read more » | about 10 years ago | |||
| cfastie | "I think most small Powershots use an IR block filter that is 8.9 x 7.9 mm. That's the advertised size of the BG3 glass filter I put into an A2200 a..." | Read more » | about 10 years ago | |||
| cfastie | "I see what you mean when you say that the difference between the blue and red channels is correlated with the presence of plants. Your monochrome i..." | Read more » | about 10 years ago | |||
| cfastie | "Zorn, If you remove the IR block filter, the camera will take very strange photos because all three color channels (RGB) will have lots of NIR ligh..." | Read more » | about 10 years ago | |||
| cfastie | "Roderick, that's a really good point that the two cameras are different models and might be processing the frames differently. Someone also comment..." | Read more » | about 10 years ago | |||
| cfastie | "If you have two cameras, and your goal is NDVI or false color infrared, the best way to get what you need is one unmodified camera and one with the..." | Read more » | about 10 years ago | |||
| cfastie | "More tests are definitely merited. First, I was assuming that Carl was using a Rosco blue filter, and my original conclusions were based on that. ..." | Read more » | about 10 years ago | |||
| cfastie | "Hi Jay, This is a great example of how important it is to get a good exposure on spectral photos. You have to hit it just right to get the most in..." | Read more » | about 10 years ago | |||
| cfastie | "Would it work to have a constant width slit with an integrated neutral density gradient from 100% transmission at one end to something less than th..." | Read more » | about 10 years ago | |||
| cfastie | "This has great potential. If you add a few extra pieces of styrofoam around the top of the bell, then the whole rig will float with the camera well..." | Read more » | about 10 years ago | |||
| cfastie | "Pascal, These are some really good ideas you are proposing. I am very interested in multiple, bracketed exposures to get more dynamic range. This w..." | Read more » | about 10 years ago | |||
| cfastie | "There is not much easily accessible information in that paper, but maybe what they did is this: They removed the IR blocking filter from a camera,..." | Read more » | about 10 years ago | |||
| cfastie | "Dave, This is an excellent idea. It looks like you are able to get much more information out of typical spectra. A quick look at recent spectra at..." | Read more » | about 10 years ago | |||
| cfastie | "Most android devices support GPS (lat, long, alt). Some day, more people will be using smartphones to take aerial photos, but today, a $40 (ebay) ..." | Read more » | about 10 years ago | |||
| cfastie | "my approach would be to upload multiple images and list them off-map. The user can then select photos to display them on map. I agree, this is a g..." | Read more » | about 10 years ago | |||
| cfastie | "Vidhun, This looks impressive. The interface for uploading photos is a great place to start improving MapKnitter. The current system requires that ..." | Read more » | about 10 years ago | |||
| cfastie | "Hi Nicholas, These rigs are not nearly as indestructible as a soda bottle rig. The leg brackets are vulnerable to cracking when the legs are stress..." | Read more » | about 10 years ago | |||
| cfastie | "It is easy to find CFL spectra that are overexposed. A quick survey suggests that maybe > 3/4 of the CFL spectra at SWB have at least one peak w..." | Read more » | about 10 years ago | |||
| cfastie | "Sreyanth, I don't know the issues associated with using SWB offline. I always work offline -- taking still photos of spectra and later uploading t..." | Read more » | about 10 years ago | |||
| cfastie | "These seem to be rather obscure indices that have very specific uses. Because satellite data always includes an NIR band, and because NIR provides ..." | | about 10 years ago | |||
| cfastie | "The Infragram Sandbox allows several different types of analysis, so it's hard to evaluate your image above without knowing what analysis produced ..." | | about 10 years ago | |||
| cfastie | "Hi Sreyanth, I really like the idea of combining information from the intensity graph of a spectrum with information about which colors the peaks ..." | Read more » | about 10 years ago | |||
| cfastie | "The Visible Vegetation Index (VVI) seems to do a good job distinguishing plants from non-plants based on how green each pixel is and also on some f..." | | about 10 years ago | |||
| cfastie | "Ecta64, It looks like you were able to map green to areas in the photos with plants, so your process might have promise. If you didn't modify the ..." | | about 10 years ago |