Image Grabber - Calibration Fails

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UGMENTALCASE
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Joined: 23 Jul 2020, 10:52

Image Grabber - Calibration Fails

Post by UGMENTALCASE » 23 Jul 2020, 11:06

Hi everyone,
New on this forum hoping for some help.
I use the DAVID laser scanner software (version 3.9 I think) It has structured light functions and laser scanning functions.
Since I do a lot of photogrammetry I thought I'd try the image grabber. This function is in both laser scanner and SLS programs.
I've watched the YouTube vid of the lets scan work flow, and I can not get it to calibrate properly.

In the laser scanner program it calibrates but then I don't know how to scan the item?
In the SLS program , the same set of calibration images fail to calibrate.
They load fine and sequence through on screen, but I get a 'can't see enough targets' error - I have tried a number of views which show more targets and less targets and get the same error.
Sometimes it picks up the targets, puts the little green markers in and then fails.
Seems to act differently when you click calibrate at different times of it skipping through the sequence.

Any help would be great, is there some setting somewhere which I need to adjust? I don't know.
It would be interesting to see how nice the results are using this method.

Cheers

https://www.youtube.com/watch?v=HGImPTMMpq8

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OBNRacerMan
Posts: 173
Joined: 12 Aug 2019, 09:46
Location: Obninsk, Russia

Re: Image Grabber - Calibration Fails

Post by OBNRacerMan » 23 Jul 2020, 12:02

1. In some of the versions, David still had a choice - which calibration panels are used - the old or the new sample (respectively, old panels are needed for laser scanning, new ones for SLS).
2. Laser scanning in David is performed only against the background of the calibration panel (ie the camera must see both the angle from the panels and the object in front of them).

UGMENTALCASE
Posts: 3
Joined: 23 Jul 2020, 10:52

Re: Image Grabber - Calibration Fails

Post by UGMENTALCASE » 24 Jul 2020, 14:09

Do you think it may need the old panel?

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OBNRacerMan
Posts: 173
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Location: Obninsk, Russia

Re: Image Grabber - Calibration Fails

Post by OBNRacerMan » 24 Jul 2020, 22:23

As far as I know, the choice between the old and new calibration panels was up to the 4th version. In version 4, this choice is no longer, although the option to use a laser has not yet been removed. This means that in the 4th version the laser should work with the new version of the calibration panel. But, as I already wrote, during laser scanning, the panel should be in the same place when the calibration was performed, and the object should be in front of it.
Unfortunately, I don't have a laser right now to check ... and the 4th version of David is just there, the main program is still HP3Dscan 5.60 (this is how David began to be called after HP bought them) - there is support for two cameras that were not in version 4

UGMENTALCASE
Posts: 3
Joined: 23 Jul 2020, 10:52

Re: Image Grabber - Calibration Fails

Post by UGMENTALCASE » 25 Jul 2020, 07:49

Hi, yes the laser needs to see the panels as its scanning you're right. Not sure if this is the issue though with image grabber?
I've noticed between the laser scanning app and sls app (which has laser scanning option) the sls app is very fussy about it yet the laser scanning app isn't.

I'm wondering if this might be the issue with the image grabber in the sls app.

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OBNRacerMan
Posts: 173
Joined: 12 Aug 2019, 09:46
Location: Obninsk, Russia

Re: Image Grabber - Calibration Fails

Post by OBNRacerMan » 25 Jul 2020, 09:48

Unfortunately, I cannot help you in this matter, I have tried laser scanning only a few times ... and that was about two years ago. After that I switched to classic SLS and never returned to laser scanning in the same way as it was with David.

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