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Author Topic: Minimum size of calibration pattern and near limit of camera  (Read 4033 times)

rexsham

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Hi,
We need to calibrate a Full Frame DSLR Camera using 35mm lens for aerial survey.
We will fly at a height of 300m so we set the focus to a point that the subject distance is 300m and the near limit of Depth of field is around 5m.

That means within a 5m distance, our camera will not be able to acquire a sharp image.
I see that the lens calibration software is using the monitor to display the checker board, since the monitor is small, if I use this lens focus ring setting to calibrate, I will get a blurry result if I do not turn the ring to refocus on the screen.

I want to know, if the calibration still works if I calibrate with the same focus ring setting for a 300m subject and acquire a blurry image of the checker board or should I turn the focus ring to make a sharp image when doing the calibration?


rexsham

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Re: Minimum size of calibration pattern and near limit of camera
« Reply #1 on: July 05, 2014, 11:51:10 AM »
Another way of asking the question is:
Will turning the focus ring affect the calibration results?

Jamin

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Re: Minimum size of calibration pattern and near limit of camera
« Reply #2 on: September 03, 2014, 12:30:41 AM »
I too would like to know the answer to this.

I'm working with a d810 coupled to a 28mm...infinity focus would require a massive checkerboard....