| Author | Comment | Last activity | Moderation | ||
|---|---|---|---|---|---|
| suman | "Can i know the real use of adding the filters....just taking off the infrared filter and getting RGB IR channels and separating those channels late..." | Read more » | over 7 years ago | |||
| cfastie | "Finding inexpensive, do-it-yourself calibration targets is an obstacle to NDVI calibration. You need targets for which the spectral reflectance is ..." | Read more » | over 7 years ago | |||
| J_tanna | "@cfastie sample image is like this, " | Read more » | over 7 years ago | |||
| J_tanna | "@cfastie On an agriculture land, How can we specify the targets for calibration? " | Read more » | over 7 years ago | |||
| cfastie | "Here is my discussion of calibrating NDVI images: https://publiclab.org/notes/cfastie/05-01-2016/calibration-cogitation And Ned's most recent note..." | Read more » | over 7 years ago | |||
| J_tanna | "@cfastie Thank you for your time. I have two more doubts in my mind, 1.) What are the steps that I need to apply for image calibration? 2.) What is..." | Read more » | over 7 years ago | |||
| cfastie | "With a blue filter which blocks only red light, the red channel will capture NIR. Use the red channel for NIR and the blue channel for visible ligh..." | Read more » | over 7 years ago | |||
| cfastie | "With a blue filter which blocks only red light, the red channel will capture NIR. Use the red channel for NIR and the blue channel for visible ligh..." | Read more » | over 7 years ago | |||
| J_tanna | "@cfastie What should be the formula of NDVI for NIR camera as it is blocking red light. " | Read more » | over 7 years ago | |||
| Claytonb | "@Thorsten I have not tried using a chart like the color checker though I have used materials(plastic, felt, paper) in the shade of red on the chart..." | Read more » | about 8 years ago | |||
| Thorsten | "@Claytonb great work as usual! Two questions: Have you tried some reddish colors of calibration targets such as the ColorChecker? http://xriteph..." | Read more » | about 8 years ago | |||
| cfastie | "This is a great discovery. It will be good to learn how this color works with a red filter like Wratten 25. I will keep my eye out for Boom Chicka ..." | Read more » | over 8 years ago | |||
| cfastie | "See the instructions for how to enter webcam mode of the Mobius camera: http://www.mytempfiles.info/mobius/MobiusManual.pdf The white balance look..." | Read more » | over 8 years ago | |||
| ino | "I will be attending! " | Read more » | over 8 years ago | |||
| LaPa | "I'm happy for this my first step in NIR and NDVI photograph! Maybe you know but ..... 1) I use not a real camera but a computer board (Raspberry Pi..." | Read more » | almost 9 years ago | |||
| cfastie | "That looks pretty good. With the defaults in the photo monitoring plugin, the plant leaves have an NDVI value around 0.3. We don't know what the ND..." | Read more » | almost 9 years ago | |||
| LaPa | "HI, What do you think about my last test? NoIR modulo cam+blue filter, WBgain red = 0.88 and WBgain blue = 0.57 " | Read more » | almost 9 years ago | |||
| LaPa | "I'll try to get blue > 30 and red < 200 changing the gain. At the moment I do not know how change the exposure. May be I have to read better ..." | Read more » | almost 9 years ago | |||
| cfastie | "Here is the range of NIR:VIS ratios for NDVI values between 0.2 and 0.8. " | Read more » | almost 9 years ago | |||
| cfastie | "That looks promising. I guess that PiCamera module is a useful tool. I think that photo is a little too yellow. The blue values for foliage are ver..." | Read more » | almost 9 years ago | |||
| LaPa | "Hi, I'm here again! I shoot a set of pictures by NoIR modulo cam and blue filter. I tryed finally different white balance. The photo that I post i..." | Read more » | almost 9 years ago | |||
| cfastie | "I don't know the specs of the blue paper I use for custom white balance. The idea is to flood the blue channel with light (when using a blue filter..." | Read more » | almost 9 years ago | |||
| carolccarvalho | "@cfastie, I'm trying to do the white balancing manually using a Raspberry Pi and I need to know the number of this "pure blue" that you are using. ..." | Read more » | almost 9 years ago | |||
| cfastie | "I think the Public Lab Store will ship filters to Europe: https://store.publiclab.org/collections/diy-infrared-photography/products/infragram-diy-f..." | Read more » | almost 9 years ago |