A case study on sub-pixel interpolation

I’m a skeptic when it comes to making sub-pixel measurements. I like to use several pixels to find an edge and I’m not sure about trusting the math involved in making repeatable measurements to less than one pixel.

But with all that said, Ben Dawson of Dalsa has written an excellent exposé of a high precision gauging system based on sub-pixel measurements. There’s a lot of technical detail in “Measure Precisely with Machine Vision,” (Vision & Sensors Magazine, November 30th, 2009,) so read it carefully, especially the part where he talks about blurring being a good thing.

I’m not 100% convinced – I still say you should throw pixels at the job if you can – but kudos to Ben for providing a very informative article.