Calibration panels for David 5

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Shefajs
Posts: 12
Joined: 07 May 2019, 13:27

Calibration panels for David 5

Post by Shefajs » 06 Jun 2019, 15:40

Hello,

Would anyone know where the calibration data is saved in the HP 3D scan software.
Since the console for the David 5 is not accessible the same as in David 4 the command line does not show the output of David server and I do not see the calibration values.

I have made calibration panels using several different printable films and hard aluminum and PlexiGlass plates. But I have nomeans of testing which is actually better since I do not see the RMS value.

Also can someone explain here each of the calibration values?

I usually have problem with calibrating on the extra small panels and I think that it was because in such sizes any parasitic warp/offset/angle between the two sides of the calibration panel matters the most.

Also since my projector is 16:9 I get significantly worse scan size problems on the sides of the scanned items then in the middle.

Any advice is welcome.

User avatar
Micr0
Posts: 328
Joined: 15 Nov 2016, 15:20

Re: Calibration panels for David 5

Post by Micr0 » 07 Jun 2019, 14:05

The console is available in v5. I use it every time I calibrate. You have to enable it's display in the settings but it's there. I can't remember the exact settings off the top of my head.
µ

Shefajs
Posts: 12
Joined: 07 May 2019, 13:27

Re: Calibration panels for David 5

Post by Shefajs » 12 Jun 2019, 10:17

Yes, thank You. Somehow I could not find that option before, but it is there.

Would You have a short description for the calibration values there that are available in the output?

I want to make sure that my calibration panels are in top shape and then I can jump in finding the best projector lenses...the ones I currently use have very shallow DOF. I'm even not sure what exactly I'm looking for in case of projector lens. It seems for me with such a small screen size any lens generate very shallow dept of focus and if it's like in the photography, I need to incorporate some shutter (or better use lens with shutter) to reach a good focus on the whole scanning area.

Shefajs
Posts: 12
Joined: 07 May 2019, 13:27

Re: Calibration panels for David 5

Post by Shefajs » 12 Jun 2019, 11:43

Ok, with the ability of seeing output I see that every time my calibration fails it's because of Projector calibration.
Would anyone know what the values means?

Apparently the values:
cy=x rmsError=.....
If it's over 3% the calibration fails.
Also there is many notes about: "3971 outliers removed (total 10042)"
I also have no idea that that means.

I'm attaching here a good and failed calibration outputs:

a Good one:

Code: Select all

     -> Setup is 'inner corner'
 - RMS error is ok: 0.49434
Camera 0 [2F37-INOGENI 4K2USB3 (CAA8201E)] calibrated:
<camera_model>CameraModelTsai</camera_model>
<cx>694.46250233802470575</cx>
<cy>254.71564382834350226</cy>
<f>5141.0940203602331167</f>
<sx>1</sx>
<kappa1>1.2878396546729133724e-08</kappa1>
<resX>1920</resX>
<resY>1200</resY>
<nx>0.85893482655903841128</nx>
<ny>0.088641885313166551841</ny>
<nz>-0.50435461720115326578</nz>
<ox>0.24366619914073883724</ox>
<oy>-0.9370065430751873814</oy>
<oz>0.25029087404576361164</oz>
<ax>-0.45039732139556531987</ax>
<ay>-0.3378777210802954567</ay>
<az>-0.82642658383989875404</az>
<px>228.50610547248487592</px>
<py>220.32354992396059856</py>
<pz>468.87381533984807902</pz>

Horizontal open angle: 21.3833
Vertical open angle: 13.3682
Calibrate Projector.
~
~
~
CalibrateProjector: leftBackPlane  = (p=1.0961e-16 1.0961e-16 24.2901 1 n=1 -0 -6.12323e-17 0)
CalibrateProjector: rightBackPlane = (p=21.3448 -0.756203 -1.41477e-16 1 n=-1.22465e-16 -0 1 0)
Angle between calibration panels: 90 degree
  Size of camera's center pixel at background plane: 0.156249 mm
cy=-0.5 rmsError=0.00228985
cy=0    rmsError=0.00228981
cy=0.5  rmsError=0.00229034
cy=1    rmsError=0.00327669
cy=1.5  rmsError=0.00327781
  3971 outliers removed (total 10042)
  3272 outliers removed (total 10042)
  3206 outliers removed (total 10042)
  3197 outliers removed (total 10042)
  3182 outliers removed (total 10042)
  3163 outliers removed (total 10042)
  3150 outliers removed (total 10042)
  3139 outliers removed (total 10042)
  3124 outliers removed (total 10042)
  3112 outliers removed (total 10042)
  3096 outliers removed (total 10042)
  3085 outliers removed (total 10042)
  3074 outliers removed (total 10042)
  3053 outliers removed (total 10042)
  3023 outliers removed (total 10042)
  2997 outliers removed (total 10042)
  2988 outliers removed (total 10042)
  2972 outliers removed (total 10042)
  2951 outliers removed (total 10042)
  2936 outliers removed (total 10042)
  2903 outliers removed (total 10042)
  2883 outliers removed (total 10042)
  2843 outliers removed (total 10042)
  2787 outliers removed (total 10042)
  2741 outliers removed (total 10042)
  2675 outliers removed (total 10042)
  2624 outliers removed (total 10042)
  2583 outliers removed (total 10042)
  2624 outliers removed (total 10042)
~
~
~
<camera_model>CameraModelTsai</camera_model>
<cx>0.49312000235917669011</cx>
<cy>-1.6033130045866945679</cy>
<f>3.4381455801201235012</f>
<sx>0.6521535513494068903</sx>
<kappa1>0.00034616040320981626309</kappa1>
<resX>1</resX>
<resY>1</resY>
<nx>0.64119887786291240861</nx>
<ny>-0.078266799282426760542</ny>
<nz>-0.76337298036898459941</nz>
<ox>-0.13232243708049518105</ox>
<oy>-0.99116097336803943296</oy>
<oz>-0.0095235244105892069566</oz>
<ax>-0.75588013049187918746</ax>
<ay>0.10711784632919491012</ay>
<az>-0.64588775752863958335</az>
<px>393.03786299608424315</px>
<py>221.11512232265954481</py>
<pz>322.09453590716373128</pz>

Saving C:\Program Files\HP 3D Scan 5\Settings\UserSettings.xml ...done.[/size]
And a BAD one here:

Code: Select all

[size=85]     -> Setup is 'inner corner'
 - RMS error is ok: 1.13708
Camera 0 [2F37-INOGENI 4K2USB3 (CAA8201E)] calibrated:
<camera_model>CameraModelTsai</camera_model>
<cx>1675.5745305974949133</cx>
<cy>-357.42094253654323666</cy>
<f>5239.1853775690879047</f>
<sx>1</sx>
<kappa1>1.3982554286780788986e-08</kappa1>
<resX>1920</resX>
<resY>1200</resY>
<nx>0.93406782788451125921</nx>
<ny>0.15857289403489085999</ny>
<nz>-0.31995613791347976562</nz>
<ox>0.20836305270023280922</ox>
<oy>-0.96967821270778375986</oy>
<oz>0.12770670330596339825</oz>
<ax>-0.29000367442594660039</ax>
<ay>-0.18595376058912244099</ay>
<az>-0.93878595416751542402</az>
<px>216.50726528042105201</px>
<py>210.0575789406438787</py>
<pz>473.0442616691232729</pz>

Horizontal open angle: 20.9821
Vertical open angle: 13.1188
Calibrate Projector.
~
~
~
CalibrateProjector: leftBackPlane  = (p=1.40621e-16 1.40621e-16 24.7965 1 n=1 -0 -6.12323e-17 0)
CalibrateProjector: rightBackPlane = (p=21.1334 -1.65407 -1.67357e-16 1 n=-1.22465e-16 -0 1 0)
Angle between calibration panels: 90 degree
  Size of camera's center pixel at background plane: 0.150827 mm
cy=-0.5 rmsError=0.00212618
cy=0    rmsError=0.00212664
cy=0.5  rmsError=0.00720476
cy=1    rmsError=0.00387285
cy=1.5  rmsError=0.00387538
  6158 outliers removed (total 10092)
~
Projector calibration failed![/size]

User avatar
Micr0
Posts: 328
Joined: 15 Nov 2016, 15:20

Re: Calibration panels for David 5

Post by Micr0 » 12 Jun 2019, 12:57

BigBomber hasn't been around recently, but he might be the one to ask about this.
µ

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