Looking at how Scan Volume and Flatness change with Standoff

Scanner Standoff affects the Scan Volume, Accuracy, and Resolution. With the latest version of Revopoint Revoscan, the scan preview window shows you more than the actual 3D Scan. The software now only provides the best calibrated data. I thought I’d make a chart showing the POP2 Scan Area versus the Scanner Standoff. I used a flat white plate to demonstrate the Scanner FOV (Field of View). I also Best-fit the data to a Plane and calculated the flatness error.

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Thanks are going to the trouble of researching and putting this film together.

I found it very fascinating.

Do you have a link to the " free" on shape software?

You made your point because that is what is happening with structured light .
But all you measured in your charts was the level of noises your plate produced in the process on a single frames .

You don’t believe me ?
here are actually multiple frames moving in Body mode meshed at 6 no denoiser

and the way you did, shooting couple of frames on a static tripod with a gain over the charts

do you see the difference ? a huge difference not only in flatness but also volume and noises , that goes for each mode you are using .

I was trying to show the POP2 field of view at different standoff distances. If you look at the color error maps you can see more than just noise. There is sort of a fish eye error. The error is worse away from the center. Usually this is due to a simpler lense distortion model/calibration. I would expect the noise/error to be worse in moving scans. My turn-table error tests show accuracies in the 0.2-0.3mm range ( Revopoint POP2 3D Scanner Accuracy Test on Turn-table using Step-Block - YouTube ) for small objects on the turntable.

It’s in the youtube video description

Of course there is difference in standoff distances as with any 3D scanner that using this technology , I told you you made your point .
I wanted to add also that the surface is calculated differently when moving vs still , I am suspecting that the fish eye effect is due to reflection from the IR on your plate , since when I captured the IR on the surface with my photo camera for evaluation the effect was similar , it was looking like a water ripple effect , but that came from the IR directly and not from the Depth Sensor cameras.

I also believe that since you early tests , something changed in the software and the still capturing of the frames is different and no more smooth as it once was , I have lots of scans that I captured this way that has crispy details but now no more . maybe the frame alignment changed since there was some problems in early builds. As you saw from my images today, still frames do not produce smooth results no more at 40 cm and beyond.
I am going to scan full body scans this weekend at 40+ distances hoping there will be no noises at that level as that would be little disappointing.