infrablue
infrablue


Author Comment Last activity Moderation
agustin_castellano "Hi Ned thanks for your research! Is great this information. i have two doubts. First if i use a red filter how should be the formula (blue - red) ..." | Read more » over 8 years ago
agustin_castellano "Hi Andresc4, i would like be in touch with you.i'm researching about the same like you. I live in Argentina. Please contact me my email agustin.cas..." | Read more » almost 9 years ago
fjcaceres "Hi Pat Thanks for your suggestion on the Forum address I bought a Canon A1200 just like you, and two filters from Cris, one of them the Wratten25..." | Read more » almost 9 years ago
patcoyle "I'm still around, but don't have special insight to the points you raise. Consider posting your observations and questions to the PL plots-infrared..." | Read more » almost 9 years ago
fjcaceres "Hi there The last post is over a year old so I don't know if there is anyone around to comment I am new to the IR NDVI scene and along many of the..." | Read more » almost 9 years ago
cfastie "Stretching the histograms of either the NIR or VIS (or both) channels used to make NDVI is a trick that can produce more meaningful NDVI. I don't k..." | Read more » almost 9 years ago
kykytos "@cfastie What do you mean with 'stretching the histogram of the infrablue photo'? Because if it means to reduce blue levels (increase NDVI levels),..." | Read more » almost 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 » almost 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 » almost 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 » almost 9 years ago
warren "The colormap is based on one of yours: " | Read more » almost 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 » almost 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 » almost 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 » almost 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 » almost 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 » almost 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 » almost 9 years ago
Tbtouaki "Hi I have tried several white balance options before, base on what I've read. On this pics the settings were exactly the same as the maxmax camera...." | Read more » almost 9 years ago
Tbtouaki "Hi Sorry for the trouble but how did you proceed to calibrate individual bands to reflectance before calculating NDVI? Did you use "dark object sub..." | Read more » almost 9 years ago
cfastie "Hi Rita, Your photo above (NIR1_Red3_b.jpg) will not produce very good NDVI. Most of the pixels of plants have the same value in each of the three ..." | Read more » almost 9 years ago
Tbtouaki "Hi I currently have a modified canon (IR block removed) with a wratten 25A Red filter. My pictures are really nice looking but I have big problems ..." | Read more » almost 9 years ago
bwarzak "Ned, Our company is supposed to be writing an article for Vision System Design magazine regarding uses for dual band filters. I realize that the r..." | Read more » about 9 years ago
Thorsten "I had no problems with using lens filters so far. But it would be interesting if there is some reason to better replace the IR Filter instead. " | Read more » about 9 years ago
nedhorning "I don't have experience with lens mounted filters but you might get some feedback if you post your question on the plots-infrared list at http://pu..." | Read more » about 9 years ago