Author | Comment | Last activity | Moderation | ||
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utobolearning | "other two images - they are more or less equal among the three channels as the camera can only see NIR. Can you think of any explanation? Why wou..." | Read more » | about 4 years ago | |||
kumarvirendran | " This is one the best blog for health. we are here give health-related best information. Those give you better health solution, which can be helpfu..." | Read more » | almost 6 years ago | |||
nedhorning | " I can think of two possible reason. The most obvious would be that the illumination changed and the other is that the sensor temperature change. S..." | Read more » | almost 6 years ago | |||
Corymbia | "Thank you both, I really appreciate your help. My tiles were far from perfect, but from next week on I will be able to test with six Spectralon sa..." | Read more » | almost 6 years ago | |||
cfastie | "Subtracting the blue channel from the red channel is a good first step for correcting for contamination of the red channel with NIR. With one parti..." | Read more » | almost 6 years ago | |||
nedhorning | "It's good you discovered that. Yesterday I started to write about the need to subtract the blue band (NIR) from the red band (red + NIR) so you get..." | Read more » | almost 6 years ago | |||
Corymbia | "Hi, I have some trouble previewing my processed DNG images in Matlab, but the channel values are similar to the ones in your image. Since the red c..." | Read more » | almost 6 years ago | |||
nedhorning | "I used this following dcraw command: dcraw -D -W -4 Image1.ORF to create this image which has been scaled to 16-bit integers: https://drive.googl..." | Read more » | almost 6 years ago | |||
nedhorning | " I have to run out now but will try to make time to check this in the morning. It's also possible it's due to the nature of the filter and after ca..." | Read more » | almost 6 years ago | |||
Corymbia | "Sure, I've just uploaded ORF files for all three images to the google drive (link at the end of my post). Unfortunately I couldn't find any inform..." | Read more » | almost 6 years ago | |||
nedhorning | "Can you post one of your RAW images? I looked at Image1.dng and that shows the Bayer pattern so it needs to go through a debayer process to create ..." | Read more » | almost 6 years ago | |||
Corymbia | "How do you make sure the white balancing step is omitted? I tried that myself (see table 3 and figure 5 in my note), but the resulting NDVI values ..." | Read more » | almost 6 years ago | |||
nedhorning | "I use RAW pixel values for calibration analysis and since white balance doesn't impact RAW values I don't usually worry about it. If you want to us..." | Read more » | almost 6 years ago | |||
Corymbia | "Thanks, I will try! One more problem I noticed yesterday was that (at least when I set the white balance on a red/white surface) the red channel g..." | Read more » | almost 6 years ago | |||
nedhorning | "The calibration coefficients are, in the simplest case, the slope and y-intercept of the linear regression line for wavelength (based on calibratio..." | Read more » | almost 6 years ago | |||
Corymbia | "Thanks for the advice. How are the calibration coefficients calculated? I need to take photos of >50 trees in a glasshouse, so even within one s..." | Read more » | almost 6 years ago | |||
nedhorning | " If you're using them for calibration you should be fine taking photos of the targets every so often. The calibration coefficients shouldn't change..." | Read more » | almost 6 years ago | |||
Corymbia | "I realised that my tiles may be too shiny and grabbed some matt paint samples (pieces of matt paper) from a local store. They’re small and light, m..." | Read more » | almost 6 years ago | |||
nedhorning | "I just read over Rob Sumner's RAW guide and see Adobe DNG Converter is free. It also looks like he did some pretty rigorous tests so my previous co..." | Read more » | almost 6 years ago | |||
nedhorning | "The tables look great. Before the end of the week I'll try to compare your converted image with on that I run through dcraw to see if they are simi..." | Read more » | almost 6 years ago | |||
Corymbia | " Hi Ned, Thanks for your comment, it was mainly your notes that inspired my camera conversion :) I (hope I) fixed the tables by inserting print sc..." | Read more » | almost 6 years ago | |||
nedhorning | " Hi Corymbia – It’s nice to see some new work in this area. I see that you used the Adobe DNG converter. You might want to look into that to under..." | Read more » | almost 6 years ago | |||
Corymbia | "Hi Chris, I made a simple test earlier today, so far only managed to look at the JPEG file data (I have an old code for reading DNG into Matlab (ba..." | Read more » | almost 6 years ago | |||
cfastie | " One photo every 50 shots might be sufficient. It depends on how much the light changes during that time (5 minutes?, an hour?, a day?). You might ..." | Read more » | almost 6 years ago |