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 » over 10 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 10 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 10 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 10 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 10 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 10 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 10 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 10 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 » almost 11 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 » almost 11 years ago