Hello, I cannot generate the reflectance map.
I use a Canon S110 NGB
I have tried to use different images to calibrate, to select smaller or bigger areas and event when I select “No Correction” I get the error.
This is the error:
[Error]: Unable to compute radiometric target calibration for CanonPowerShotS110_5.2-26.0mm_5.2_4000x3000 NGB (NIR,Green,Blue) with D:/Fotogrammetria/Santarem mapeamentos março 2017/SD complete/NGB/103_2403/volo03/IMG_0932.JPG: Too many invalid pixels (99.1615% > 5%) for band 0
Thank you
It looks like the calibration image is overexposed. It is not possible to use an overexposed image for radiometric calibration. When choosing the No Correction method, the information is not taken into account, but it could be that the software does the check in any case. If you create a new project and do not input any calibration image (you could choose the Camera Only radiometric corrections in this case), it should process correctly.
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How can I prevent overexposure, and my calibration whiteboard will be overexposed every time 
thanks.
Hey Xinyang,
Do you have other calibration images? Maybe you can try to swap the calibration images. Alternatively if you click on calibrate, you can draw your own area for the calibration target. Instead of using the default area, if you create your own are that is neither over-exposed not under-exposed you may be able to use the calibration target.
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Hello,
You would need to change the camera settings to make sure that the image is not overexposed (exposure time, for example). Alternatively, you could use a lighter background behind your target (for example we typically take it over light colored asphalt), but we would privilege changing the camera settings.
Best regards,
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