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Unable to calibrate previously uncalibrated images

In the past, when an image was incalibrated it was possible to use a mixture of manual tie points, ground control points, and verified automatic tie points to calibrate the image. In newer releases (not sure when this started), if an image is uncalibrated on the first run-through, it no longer generates automatic tie points and does not seem to be included a new AT. The image will show only manual tie points and ground control points, but no matter how many tie points I add, it will not calibrate. This has happened across many projects and different cameras/platforms now.

What’s going on here?

You need to manually calibrate the images :

https://support.pix4d.com/hc/en-us/articles/202560189-How-to-manually-calibrate-uncalibrated-Cameras-in-the-rayCloud#gsc.tab=0

It takes a bit of guesswork to see which points are ‘calibrateable’ but bacsically the program has got the points mixed up with other points. Once you show which ones are correct it will calibrate the image. You then need to reoptimise to ‘fix’ the calibration and images to the model.

I can’t manually calibrate it because the processing ignores the images totally and does not potential generate tie points at all. This is the problem.

Try to fly the mission again with more  overlap and 2  paths rather than one,

I’ve found the software works best if you have at least 3 flight lines. I made the mistake in the past of flying a small, linear site with only one flight line and it was very difficult to properly orientate. I must have run Step 1 a dozen times and probably just got lucky it worked. An extra few minutes of flight time can save hours of manual editing in the office.

Hey Wesley,

What calibration method are you using? If you haven’t done so try using the Alternative calibration method and 0.5 image scale, those two methods would help you to get more images calibrated.

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