Author | Comment | Last activity | Moderation | ||
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ektopyrotic | "Dual bandpass filters used on the modified DJI Mavic 2 Pro Full-Spectrum Hasselblad can be purchased here: Both Types of Filters for sale here: ht..." | Read more » | about 1 year ago | |||
batuhanbozuntu | " Php Script " | Read more » | over 4 years ago | |||
cfastie | "Setting a custom white balance on the Mobius camera can be done numerically. Determining which numbers to use requires trial and error and subjecti..." | Read more » | over 7 years ago | |||
suman | "Dear Cfastie, Very informative. Thanks for posting. I was interested to know, which method is more preferred and accurate, whi..." | Read more » | over 7 years ago | |||
WhiteRabbit | "Interesting results! " | Read more » | over 10 years ago | |||
cfastie | "You're right, that would be a revealing test. In the example you referred to (below), the red channel should be three times more sensitive than th..." | Read more » | over 10 years ago | |||
ttaylor | "you know, if the little color filters in Mobius cmos sensor Bayer array have the same spectral response as some of the CCD sensors I've seen around..." | Read more » | over 10 years ago | |||
ttaylor | "Wow, that was quick. Too bad about the Mobius not doing raw. I feel like a I have decent handle on the Canons, but the Mobius is so light and po..." | Read more » | over 10 years ago | |||
cfastie | "Tom, Maybe it would also be useful to you to have DNG images (via CHDK) from my full spectrum Canon A810? " | Read more » | over 10 years ago | |||
cfastie | "Hi Tom, I didn't capture RAW with the S95, and the Mobius does not do RAW (although the firmware is open source, so it's possible). I could capture..." | Read more » | over 10 years ago | |||
ttaylor | "Chris, do you have raw versions of these images I could look at? " | Read more » | over 10 years ago | |||
mathew | "I'm matching your process from here- got to go grab the rosco filter packs from storage, but I just printed up that beautiful mount. " | Read more » | over 10 years ago | |||
mathew | "I'm surprised at the IR passing of the Powershot. nice research. really should buy some of those NIR LEDs myself. " | Read more » | over 10 years ago | |||
warren | "...the plant pixels will have the biggest values for both R and B and the difference between them is therefore likely to be bigger. Yeah, the idea..." | Read more » | over 10 years ago | |||
PeeBee | "Thanks cfasie. I understand now the exposure issue you raise. But you seem to assume the different exposures are an unknown, which it strikes me ..." | Read more » | over 10 years ago | |||
cfastie | "To compute NDVI, you have to know the relative amount of light in a visible and an NIR band being reflected from plant leaves. The difference betwe..." | Read more » | over 10 years ago | |||
air_maiden | "I too am interested to see whether a non-modified camera and a camera with the IR filter removed can be used to calculate NDVI. Could you please cl..." | Read more » | over 10 years ago | |||
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 » | over 10 years ago | |||
PeeBee | "Thanks cfastie. I don't think I understand the need for the Wratten filter. My understanding is: A camera with just the IR filter removed (i.e. n..." | Read more » | over 10 years ago | |||
ttaylor | "Ned, each "red" pixel in a 2x2 block typically has an intensity about 50% bigger than the either of the two "green" pixels in the same block. The t..." | Read more » | over 10 years ago | |||
nedhorning | "Nice post. It would be neat to characterize some of these cameras. I made a half-hearted attempt a while back to access the necessary equipment but..." | Read more » | over 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 » | over 10 years ago | |||
warren | "In short, while you've clearly shown there is IR in all 3 channels, there is still a reasonably good signal/noise ratio difference between 2 channe..." | Read more » | over 10 years ago | |||
warren | "Thanks Chris, but I'm not sure I agree that we're just seeing brightness due to infrared. I'm not saying this is NDVI -- it seems to work in the re..." | Read more » | over 10 years ago |