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3 canera 1 projector

The place for questions, problems, comments and tips regarding the camera calibration.

3 canera 1 projector

Postby ralphidlisan » Mon Dec 09, 2013 11:53 pm

please help,
is it possible to have 3 camera with different focus but only 1 projector? because whenever I load the saved calibration and I change the focus of the projector but camera focus is just the same then scan the result is skewed.

and I just want to ask what are different camera for the image grabber and video grabber?
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Re: 3 canera 1 projector

Postby MagWeb » Tue Dec 10, 2013 1:03 am


not sure what you have in mind. Could you post an image of the setup you try to do?

A SL calibration calculates the cam's position towards a know object (means the corner), its parameters, as focal length and lense distortion, AND the position of the projector and its parameters.
To use a saved calibration without some distortions the ratio of projector and cam have to be the same as they were doing the calibration. This means that you can not change anything in this ratio: Neither the distance between cam and projector, nor anything on the optics of both devices and nor anything in the SL advanced settings.
It should be possible (never tried this) to make a fixed rig with 3 cams which do NEVER change its positions towards the projector which also has to keep its focus settings .
On such a rig you should be able to calibrate cam1 and its ratio to the projector and save it as "cam1" "pro1", do the same with cam2 saving as "cam2" "proj2" and cam3 as "cam3" "proj3".
But this seems to be rather difficult and time consuming...
Maybe I got you wrong.

Edit: With the image- or moviegrabber you can load recorded images or a movie. This is some kind of postprocessing which has to be calibrated the same way...
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