Few questions about ScanCenter

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OBNRacerMan
Posts: 372
Joined: 12 Aug 2019, 09:46
Location: Obninsk, Russia

Re: Few questions about ScanCenter

Post by OBNRacerMan »

The top of the plate is completely flat. In the process of modeling, I only set the angle of inclination of the paws to 10.65 ° (I repeat, this angle value, I did not measure it myself, but read it in our 3D scanning chat).
top view
top view
bottom view
bottom view
and
installed quick release
installed quick release
Soft: RangeVision DIY, Calibration panel/Rotary tables - RangeVision, Prj: LG PF1500G, Cam: Daheng Mercury MER2-630-60U3M-L (USB3.0, monochrome) x2, Obj: ZLKC FM12036MP5 (F2.8/5Mp/12-36mm) x2. And a handheld scanner Creality Ferret
mdesign
Posts: 37
Joined: 03 Jan 2022, 14:51

Re: Few questions about ScanCenter

Post by mdesign »

Thanks for unscrewing your projector for me.

This is strange because the rear thread distance is not the same height as the rear leg. So the angle of the projector is different than during measurements (the projector looks higher than it would stand on both legs).

I`m confused more now.
dfgdf.jpg
Have you built your rig alone? Have you some 3d/CAD template for this?
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Micr0
Posts: 586
Joined: 15 Nov 2016, 15:20
Location: New York City

Re: Few questions about ScanCenter

Post by Micr0 »

This is my 3D printed projector mount. It has an adjustable inclination to accommodate different projectors.
IMG_20180514_170255.jpg
PXL_20201204_193106334.NIGHT.jpg
µ
erol
Posts: 49
Joined: 07 Oct 2017, 17:08

Re: Few questions about ScanCenter

Post by erol »

This is my new scanner mount. :D
Attachments
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photo_2022-05-05_16-09-04.jpg
photo_2022-05-05_16-09-04 (2).jpg
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mdesign
Posts: 37
Joined: 03 Jan 2022, 14:51

Re: Few questions about ScanCenter

Post by mdesign »

Micr0 wrote: 20 May 2022, 15:07 This is my 3D printed projector mount. It has an adjustable inclination to accommodate different projectors.
erol wrote: 20 May 2022, 18:43 This is my new scanner mount. :D
Could you tell me how you calculate the projector angle
and what angle you use for LG HF60LS? Do you use also 10.65 degrees angle or have you calculated other value for that scanner?
erol
Posts: 49
Joined: 07 Oct 2017, 17:08

Re: Few questions about ScanCenter

Post by erol »

At first, I started the drawings by setting it to 10.65 degrees, then I made the angle variable. If you mount your projector in such a way that you can change the angle, you can change the angle of the projector (the mounting bracket on the bottom of the projector) to align it with the cameras. Thus, there is no need to calculate the angle.
mdesign
Posts: 37
Joined: 03 Jan 2022, 14:51

Re: Few questions about ScanCenter

Post by mdesign »

erol wrote: 20 May 2022, 19:44 At first, I started the drawings by setting it to 10.65 degrees, then I made the angle variable. If you mount your projector in such a way that you can change the angle, you can change the angle of the projector (the mounting bracket on the bottom of the projector) to align it with the cameras. Thus, there is no need to calculate the angle.
but without that, you can`t be sure that the angle between the camera direction and the line from the centre of the projector lens to the middle of thrown screen height will be parallel.

It should be that (maybe I`m wrong):
sdfdsfsdf6.jpg
When you set angle randomly only to meet thrown screen centre and camera centre:
jhkhjkhjkh.jpg
I`m wondering if that angle 10.65 is important or not because after looking at your setup and your last post I see that you only meet the projector and camera centre on some random angle (only to meet both in one place). Do you use ScanCenter on that setup?
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OBNRacerMan
Posts: 372
Joined: 12 Aug 2019, 09:46
Location: Obninsk, Russia

Re: Few questions about ScanCenter

Post by OBNRacerMan »

At my working distances (0.25m - 0.9m), the coincidence of the projector and cameras is quite good. However, here it depends a lot on specific instances of both the projector and the cameras. Since I know that, for example, in the finished Rangevision Pro scanner, there is the possibility of adjusting the vertical angles of the cameras for fine tuning.

As for my files, I model everything in 3dsmax, so I can only give the final STL files for further modeling in any CAD.

Link to my file archive
General form
General form
Modified rotating camera base
Modified rotating camera base
Shortened legs
Shortened legs
There is a basic version, and two files of subsequent improvements, mainly related to the installation of new lenses.

Also keep in mind that I am using a rail guide with roller carriages.
Soft: RangeVision DIY, Calibration panel/Rotary tables - RangeVision, Prj: LG PF1500G, Cam: Daheng Mercury MER2-630-60U3M-L (USB3.0, monochrome) x2, Obj: ZLKC FM12036MP5 (F2.8/5Mp/12-36mm) x2. And a handheld scanner Creality Ferret
mdesign
Posts: 37
Joined: 03 Jan 2022, 14:51

Re: Few questions about ScanCenter

Post by mdesign »

OBNRacerMan wrote: 21 May 2022, 10:26 ...
There is a basic version, and two files of subsequent improvements mainly related to the installation of new lenses.
...
Thanks for those files. I will look carefully at it.
OBNRacerMan wrote: 21 May 2022, 10:26 ...
in the finished Rangevision Pro scanner, there is the possibility of adjusting the vertical angles of the cameras for fine tuning.
...
It could mean that perfect coincidence between cameras and projector lenses is not necessary. Because after the manual change you can't be sure what angle you really have. I`m trying to get that perfect 10.65 angles. When I need the camera to look higher then I give some small pads to screws without changing the vertical angle. I`ve thought that keeping that 10.65 angle is crucial but maybe I think about it too much.

I`ve written an e-mail to LG support to get from them factory vertical angle. I don`t think they will give me but it is always worth trying.

Thanks for trying to help me.

I`m not sure which angles are really important and which are not. It looks the perfect vertical coincidence between cameras and projector lenses is not so crucial here.

Without coincidence, I had an accuracy about 5mm per 1.5m. With almost perfect coincidence to that angle 10.65 (I had 10.62), I had an accuracy about 3mm per 1.5m but the reason for that may lay somewhere else.

Always then I see that projector angle or camera angle is regulated on screws it means for me that setting perfect angle is not so important (you can't measure what angle you have actually.
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OBNRacerMan
Posts: 372
Joined: 12 Aug 2019, 09:46
Location: Obninsk, Russia

Re: Few questions about ScanCenter

Post by OBNRacerMan »

Yes, small vertical deviations of the cameras above or below the "cross" do not affect the accuracy of the calibration and the resulting scans. This is only necessary in order to maximize the use of the projection area and the field of view of the cameras.
Soft: RangeVision DIY, Calibration panel/Rotary tables - RangeVision, Prj: LG PF1500G, Cam: Daheng Mercury MER2-630-60U3M-L (USB3.0, monochrome) x2, Obj: ZLKC FM12036MP5 (F2.8/5Mp/12-36mm) x2. And a handheld scanner Creality Ferret
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