In our blog post, Tips for 3D Scanning Small Objects, we offered several tips on scanning small objects to get good results. Recently, our team received an email from Simon Stone, our UK distributor from Mech Innovation Limited. He sent us his latest 3D scanning results for a two pence coin.
Looking at the raw 3D scans we were very impressed with his results. The diameter of the coin is 25.9 millimeters and the coin details are approximately 0.1mm deep. No post-processing was done to the 3D scans. They were taken using a 3D scanning system built using FlexScan3D Software with a pair of 2 megapixel (MP) cameras and 5MP 25mm lenses. The 3D scanner can produce scans of a small object with great clarity and definition.
Simon did a similar scan back in 2009 using a pair of 5MP machine vision cameras and 5MP 25mm lenses. In the new coin scan, the projector lens was also slightly modified to allow the projector to project closer to the target object. Here is the 2009 scan (on the left) and his recent scan (on the right) for comparison.
|Cameras||5 MP USB camera CMOS,
1/2.5", 2.5um pixels
|2 MP FireWire cameras CCD,
1/1.8", 4.40um pixels
|Lens||5 megapixel 25mm lenses||5 megapixel 25mm lenses|
|Projector||Standard DLP Projector||Standard DLP Projector
with Minor Lens Modification
|3D scanning software||FlexScan3D 2.0||FlexScan3D 3.0|
What can we learn from these results?
When comparing 3D scanning systems, higher megapixel cameras do not always translate to better quality scans. A variety of factors can influence the 3D scanning results such as the quality of the camera’s sensors and how the 3D scanner is setup for a specific scan job. Rather than looking purely at the cameras' resolution (MP), the 2MP cameras have more sensitive sensors that produced far superior results compared to the 5MP camera sensors. A combination of having high quality camera sensors and image projection produced better scan quality. Usually better quality is associated with more costs. The 2MP cameras are three times the cost of the 5MP cameras.
Designing a good 3D scanner is a complicated task. Knowing which scanner settings to use often require time and practice. Investing time to learn how to operate the system will reward you with amazing results. Our team and our partners are always exploring and experimenting with our systems to get the best 3D scanning results. If you have any questions on your 3D scanning needs, please don't hesitate to contact us. We're always happy to help! :-)
This blog post was previously posted on Wed, Feb 15, 2012 on 3D3 Solutions blog. LMI Technologies acquired 3D3 Solutions on May 1, 2013. Please note that LMI Technologies no longer sells FlexScan3D Software as a separate software package. FlexScan3D software is the 3D scanning engine for HDI 3D Scanners.
Posted by Thomas Tong