calibration grid

[altran]

Hello,

I am using the NI Vision calibration grid which is (917x918) but my image I want to calibrate is 1920x1080.  How can I get this to work or is this even possible?

Thanks

[TiTou]

What software are you using? Vision Builder AI? LabVIEW?

I don't think there is a size limit, I'm pretty sure you can calibrate just about any image size.

Where have you seen that 917*918 limit?

[altran]

After I create a calibration file using the Grid image that comes with NI which is 917x918,  I try to use the Calibration file on a larger image and it gives me an error saying the image I process should be the same as the calibration file.

[BruceAmmons]

You have to print out a grid, then take a picture and use that to calibrate your camera.  Using the sample NI image won't do you any good at all.

Bruce

[TiTou · Accepted solution]

As Bruce said, the whole point of grid calibration is to calculate the "optical imperfections" of you system (camera + lens) so you take a picture with your imperfect optical syytem of a near perfect grid to be able to estimate the optical deformation of you "camera + lens".

See this :

[Hatef.fouladi]

There is no by to by relation between pixel and amount of grid just regard that 

your grid should be detectable by ccd so they should not smaller that 2time of your pixel sweeping area also how match your grid are few calibration will be week and some time will not calibration 

after calibration it is important to regard that you could not change resolution and magnification after calibration otherwise it will return error 

 so do not use calibration file for different resolution magnification and distance of abject different with gird distance 

 i hope this text could help you 
Hatef

[altran]

thank you all for your help.  I understand what the grid is used for now.  The video helped.

[Hatef.fouladi]

witch video do you means?!

[TiTou]

@Hatef : I assume it is the youtube video I posted above.