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Image Prespective Error

Hi,

 

The image of part to be inspected using camera and product in perpendicular direction.

 

1. Basler Camera :Basler acA2440-20gm

 

Sensor Format 2/3''
  Sensor Type CMOS
  Sensor Size 8.4 mm x 7.1 mm
  Resolution (HxV) 2448 px x 2048 px
  Resolution 5 MP
  Pixel Size (H x V) 3.45 µm x 3.45 µm
  Frame Rate 23 fps
  Mono/Color Mono

 

2. Lense  : Computar M1214-MP2  (f=12mm F1.4)

Sajeesh_1-1644302989031.png

 

But the image seems to be not correct towards the right end as if dilated some perspective / parallax/distortion. The image is finally used to do geometric pattern matching.

Please help to fix it or any other additional set up used.

 

Sajeesh_0-1644302070066.png

 

 

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This looks like a case where I would seriously consider a telecentric lens.  You are going to have some parallax errors with the current lens no matter what you do.  If you move the camera back and use a longer focal length lens, it would reduce but not eliminate the parallax.  A telecentric lens is the only way to completely eliminate parallax.

 

Bruce

Bruce Ammons
Ammons Engineering
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Bruce is correct that telecentric lens is the best. But the other option of moving the camera away from the object and using longer focal lens will help a lot. Should be sufficient for geometric pattern finder.  

Try to use f = 45 or similar. 

Other option is to use image calibration to correct the image before you do the processing. 

https://zone.ni.com/reference/en-XX/help/370281AG-01/nivisionlvbasics/calibrating_images/

https://zone.ni.com/reference/en-XX/help/370281AG-01/imaqvision/imaq_correct_calibrated_image/

 

Good luck

Amit

Amit Shachaf
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