Comments

Author Comment Last activity Moderation
nedhorning "Hi Roolark - I don't have a spectral sensitivity curve for the A2200. I've been using LEDs to get a rough idea of spectral sensitivity but that's a..." | Read more » about 9 years ago
nedhorning "There are gel and glass NIR-block filters that you can buy that do a pretty good job at blocking visible light. There might also be some other free..." | Read more » over 9 years ago
nedhorning "My guess is that you would get the same effect that you get with a blue card if you used a gray card and then multiply the blue channel by a factor..." | Read more » over 9 years ago
nedhorning "This white balance stuff got me thinking. I don't think the white balance actually changes the amount of light recorded by the sensor but instead m..." | Read more » over 9 years ago
nedhorning "With the Infrablue filter there is both visible and NIR light hitting the camera sensor and it would be helpful to know how different wavelengths a..." | Read more » over 9 years ago
nedhorning "Sorry for not explaining this better. We were just trying to understand which sensor channels are recording which wavelengths of light. The images ..." | Read more » over 9 years ago
nedhorning "Would the result improve if you set white balance using a neutral target? Concrete is pretty even across the visible and near IR. " | Read more » over 9 years ago
nedhorning "This isn't actually a classification. I was generating different layers from the 4-band (red, green, blue, near-IR) images collected a few weeks ag..." | Read more » over 9 years ago
nedhorning "Increasing dynamic range will go a long way in improving NDVI results in the shadows. There are some high-dynamic-range image processing methods th..." | Read more » over 9 years ago
nedhorning "Great shots. The impact of shadows on NDVI will vary with the darkness of the shadow. Lower pixel values (darker shadow) will be more likely to pro..." | Read more » over 9 years ago