Flat Surface Matching Improvement
Hello all,
I'm a new RC user and have been learning quite a bit on this forum.
I have a very predictable problem with flat surfaces. Hoping that maybe someone has suggestions for improving flow/settings/etc.
Below is an example of two photos with matches shown in full view (left) and area of interest zoom (right). As can be seen, RC identifies matches in the photos but not on the "white box", even though there are some features on the box (dirt specs, masking tape, etc.) The tape was put on in anticipation of this problem.
Not surprisingly, most of the box is missing when the mesh is generated.
Any suggestions on improving this? Any settings I can change? Image processing tricks?
Any advice or thoughts would be greatly appreciated!
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Hi Tim,
hmmm, I agree there should be at least s o m e points at the tapes.
The best way to check if there are any tie points is the sparse point cloud.
You could try and increase Preselector Features so that more and by that weaker points will be included as well (with all the disadvantages of course). If there aren't enough, you might want to increase Detector Sensitivity or the Max Features Per Image (or Mpx).
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I tried modifying the settings as suggested. There are no visible improvements
Detector Sensitivity was already on Ultra
Max Features per Image: increased from 200,000 to 1,000,000
Preselector Features: increased to 80,000
Any thoughts/suggestions on reasonable maximum values for these settings?
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I think you just made a new record! :-)
No seriously, those are already beyond anything I've seen recommended. I think basically doubling it is already much.
If that didn't help anything and your sensitivity was already on Ultra (!?!) then I fear there are not enough features. Have you tried using the not-undestorted ones yet?
Can you share one image with the natural resolution?
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Yes! I'm all about the records, even the dubious ones
Could you elaborate on the "using the not-undestorted ones", please?
Looks like the image is too large to insert here, so here is a link to a shared version
https://drive.google.com/file/d/1KxJPcYKRY-mCiPOkPVZD5EoGM9LGF1ac/view?usp=sharing
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Hi Tim,
sorry, I seem to be confused between you and John! :-)
He said once that he did some prior undistorting of the images which I recommended not to...
Thanks for sharing - it was good that I asked though. The image shows quite severe post processing, seems like noise reduction to me. And that kills not just noise but also small details (aka features) which explains the lack thereof in RC. Do you only shoot JPG or also RAW? If Raw, then go easy on the sharpening (as in none at all) and if not, then I am afraid this is probably as good as it is going to get...
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