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Author Topic: Calibration/Accuracy possible with Photoscan?  (Read 10984 times)

3D_Scan_Fan

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Re: Calibration/Accuracy possible with Photoscan?
« Reply #15 on: March 12, 2015, 05:17:36 AM »
I see. I'm going to give it a go (with the black shell first). But about hte accuracy, am I on the right track by using those printed coded markers?

Quick question as well, can PhotoScan work with photos that were taken from a rotating turnatable??

bigben

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Re: Calibration/Accuracy possible with Photoscan?
« Reply #16 on: March 12, 2015, 06:30:37 AM »
... and what 3D printer is going to reproduce that accuracy ;)  Easiest way to explore the limits is to start with your calibration target. That will give you a quick idea of what magnification you're going to need and whether or not it's going to be practical.

Is this calibration target a way for getting accurate measures? or to do with the camera's lens due to distortion? I've printed these coded markers from PhotoScan (they're like these incomplete circle bars with a white dot in the middle), that's the only tutorial I could find about getting and setting up scale bars and measurements.

Have you guys heard of the ProJet x60 Series Professional 3D Printers???  ;)

If you're wanting to verify precision you will need a way of providing an accurate reference on which to base you determination of the accuracy.  If you want to have 0.0001m accuracy, you will need to be able to measure an object to that degree of accuracy to compare the measurement from your 3D model.

The Projet 860 Pro is only 600 x 540 dpi resolution (0.042 x 0.047mm) whilst you started this thread asking about 0.01mm+/- accuracy (and then threw in mention of micron accuracy which is 0.001mm).  That shifts the goal posts a fair bit. 

You can use any type of marker to set up scale bars, but you will need to be able to measure the distance between points with the same level of accuracy that you need in your model.  If you really need +/-0.04mm then you will need to be able to measure distances within +/-0.04mm or have an object that has been measured to that level of accuracy.