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2014-02-24 02:16:42 -0600	commented answer	CameraCalibration -> Documentation -> Focal Lengths Thank you very much for help.
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2014-02-20 14:52:50 -0600	commented answer	CameraCalibration -> Documentation -> Focal Lengths I think I begin to understand there is my incomprehension. I do not know that is "normalized camera coordinates". Can you explain briefly that is it "normalized camera coordinates"? Or may be you know link there I can read about it?
2014-02-20 03:34:13 -0600	answered a question	CameraCalibration -> Documentation -> Focal Lengths For simplicity lets consider only Z and X. Lets Y = 0 everywhere. D(x) — it is distortion polynom x — original point coordinates (X and Zx axises) x' — it is undistorted (ideal) coordinates (X and Zx axises) x'' — it is distored (real) coordinates (X and Zx axises) v — it is distored (real) coordinates (V and Zv axises) In my opinion to calculate image coordinates (V and Zv axises) using camera coordinates (X and Zx axises) we should use these equations: x' = f * x / z x'' = D(x') v = x'' + c There is my mistake? Why in OpenCV documentation we multiply by focus at the end, but not at the begin?
2014-02-19 01:41:33 -0600	commented answer	CameraCalibration -> Documentation -> Focal Lengths Hi, jensenb. Thank you for answer. I know about distortion and understand middle rows responsible for. Question was a little bit about another aspect. We can apply distortion formula to the coordinates. For example, if x' and x'' are coordinates, than we can write x'' = DISTORTION(x') But in formulas above x' is not coordinates. It is just ratio x/z. Why x' is equal x/z? Why x' is not equal Fx * x / z?
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2014-02-16 22:59:24 -0600	asked a question	CameraCalibration -> Documentation -> Focal Lengths Hi, everyone. I have one question about FocalLenght in documentation in CameraCalibration. Now we have formula like this: $image description$ Why do we multiply by Fx and Fy in the last two rows, but not in the second and third rows? In my opinion we should use this rows: ...... x' = Fx * x / z y' = Fy * y / z ...... u = x'' + Cx v = y'' + Cy Am I right? Or I do not understand something? Can somebody help me to find error? EDIT: For simplicity lets consider only Z and X. Lets Y = 0 everywhere. D(x) — it is distortion polynom x — original point coordinates (X and Zx axises) x' — it is undistorted (ideal) coordinates (X and Zx axises) x'' — it is distored (real) coordinates (X and Zx axises) v — it is distored (real) coordinates (V and Zv axises) In my opinion to calculate image coordinates (V and Zv axises) using camera coordinates (X and Zx axises) we should use these equations: x' = f * x / z x'' = D(x') v = x'' + c There is my mistake? Why in OpenCV documentation we multiply by focus at the end, but not at the begin?