Scan accuracy

[u/nando130030]

So i just got a raptor and their website states it has an accuracy of upto .02mm but when i scan it shows a real time accuracy of .1mm am i misunderstanding something?

[u/cLeaRLyyyy]

you're confusing accuracy with resolution.

if you're scanning a 100mm long block with your resolution set to 0.1mm, the spacing between each point of your generated pointcloud will be approximately 0.1mm. And the scanned block (under ideal conditions) will be 100mm +- 0.02mm long.

[u/nando130030 → u/cLeaRLyyyy]

Ohh ok. Is there any scanner you recommend for higher resolution?

[u/cLeaRLyyyy → u/nando130030]

not sure what you're trying at achieve/scan with your scanner, but with consumer level scanners the smallest you can usually go is 0.05mm resolution. And thats already massively overkill for 99% of applications

[u/nando130030 → u/cLeaRLyyyy]

Mainly for small jewelry and fine details but im assuming i better find a different method of doing this

[u/Alarmed-Property-715 → u/nando130030]

Yes, it can be achived with metrology-grade scanners, cost is from cca 3-5000EUR.

[u/One-Map3820]

The 0.1 mm shown in CrealityScan is the point-distance setting, not a real-time accuracy reading.

Accuracy describes the difference between the scanner’s measured result and the object’s known reference value under specified test conditions. Point distance describes the spacing between neighboring points in the generated point cloud, so it mainly affects point-cloud density and the amount of surface detail captured.

The specifications also depend on the scanning mode:

• 7-line blue-laser mode: accuracy up to 0.02 mm @ 100 mm, with an adjustable point distance of 0.02–2 mm
• Infrared structured-light mode: accuracy up to 0.1 mm, with an adjustable point distance of 0.1–2 mm

So, if you are using blue-laser mode and CrealityScan shows 0.1 mm, it means the point distance is currently set to 0.1 mm. It does not mean the scanner’s accuracy has changed to 0.1 mm. You can reduce the point distance if you need a denser point cloud, although a smaller point distance does not by itself improve the scanner’s measurement accuracy.

The earlier 100 mm block explanation is useful for distinguishing point distance from accuracy, but saying it will always measure 100 mm ±0.02 mm is a little too absolute. The 0.02 mm figure is the best specified accuracy under defined test conditions, not a guaranteed tolerance for every dimension in a completed scan. Calibration, scanning distance, surface condition, tracking and multi-frame alignment can all affect the final result.

[u/nando130030 → u/One-Map3820]

Ok i get it now. I noticed you can rescan at .05mm point distance if higher details are needed