Author Comment Last activity Moderation
warren "Hi, can you share the images you do get, before and after your calibration? " | Read more » over 2 years ago
warren "@warren awards a barnstar to Claytonb for their awesome contribution! " | Read more » almost 4 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 » over 5 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 » over 5 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 » almost 6 years ago
Rural "Magic Lantern seems to run on the EOS M and has an intervalometer. I can't recommend Magic Lantern enough. I've got an EOS 600D/T3i that I much pre..." | Read more » about 6 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 » over 6 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 » over 6 years ago
funkycbj "I just used a StellarNet spectrometer to find the transmittance of hot filters from the Canon A2200 & A2500. Both hot filters rapidly fall off ..." | Read more » about 7 years ago
cfastie "Orangey yellow is good for blue filtered Infragrams. Turquoise blue is good for red filtered infragrams. Gray is bad. Below is a good red filtered ..." | Read more » over 7 years ago
liz "hey @cfastie and @warren , is it true that orangey looking photos indicate a well white balanced blue filter infragram, while blue/greyish photos i..." | Read more » over 7 years ago
nedhorning "I usually use a gray target to white balance my NIR camera but I know some people use green vegetation like grass for the white balance. You can ex..." | Read more » almost 8 years ago
gpenzo "ttaylor you make some good points there. My cameras are not on a gimbal but directly connected to the drone (pure for kiss). Because of some gust t..." | Read more » almost 8 years ago
ttaylor "Interesting work indeed. I have a few partly formed thoughts: 1) since there is a thunderstorm, the illumination conditions are highly variable an..." | Read more » almost 8 years ago
gpenzo "Good point Ned. I'm going to lock everything in those cam. Event the photos are not good I love the sharpness. Ned should I use white background fo..." | Read more » almost 8 years ago
warren "Ned, those are some great points -- would you mind if I used them as the basis of a new page at: ? " | Read more » almost 8 years ago
nedhorning "The NIR and visible images look a little different and that could be caused by a few factors. If any of the camera settings change between images i..." | Read more » almost 8 years ago
ttaylor "The alignment of the blue and red spectral response below 850nm that you are seeing is consistent with the spectral response curves that have been ..." | Read more » about 8 years ago
gpenzo "In my case I also want to capture visible images, will help the farmer to identify the problem. Can use my drone for mapping and 3d vegation maps w..." | Read more » over 8 years ago
cfastie "It's good to know about the NDRE. Instead of computing the difference between reflected NIR and reflected red light, I think NDRE replaces reflecte..." | Read more » over 8 years ago
funkycbj "Just so you know, 720nm is in the "red edge" region so you're not computing NDVI. You are computing the Normalized Difference Red Edge Index (NDRE). " | Read more » over 8 years ago
cfastie "Thanks Grayson, I was referring to stretching the histograms in the Fiji plugin. I forget what the default is, but it can make a big difference. ..." | Read more » over 8 years ago
gpenzo "Hello Chris. Seems I need to be more precise on my notes, answer to your question. NIR camera has the block filter removed. 720 and 850 nm filter ..." | Read more » over 8 years ago
Tbtouaki "Thanks that is exactly what I wanted to know. I am going to modify one camera, and wanted to test different filters, but was unsure if I could do ..." | Read more » over 8 years ago