POV-Ray : Newsgroups : povray.general : how to define the focal length and the principal point of a camera in pov r= : Re: how to define the focal length and the principal point of a camera in pov r= Server Time15 Aug 2022 08:20:15 EDT (-0400)
 Re: how to define the focal length and the principal point of a camera in pov r=
 From: Alain Martel Date: 18 Jul 2022 11:10:33 Message: <62d577e9@news.povray.org>
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Le 2022-07-18 à 09:29, 6digit a écrit :
> good evening,
>
> I recently calibrated a camera to get the intrinsic and extrinsic parameters. my
> main goal is to mimic the perspective camera in pov ray with that of the real
> one. I was wondering if it's possible to define the focal length and principal
> point of the perspective camera located in pov ray. I read through this
> documentation <http://www.povray.org/documentation/view/3.6.1/246/> but it
> doesn't seem to mention any about defining a focal length and principal point.
> any tips?
>
> thank you
>
> regards 6digit
>

The length of the direction vector determine the distance between the
camera and the projection plane. In a way, it can be seen as the focal
length of the camera.Then, the ratio between the up and right vectors
determine the aspect ratio of the image. Those three vectors should be
perpendicular to one another.

If you want to emulate focal blurring, then, you need to use the focal
blur feature. For that, you need to also define the aperture of the
emulated objective, the focal point and how many samples are to be used.
You will find the relevant information here :
https://wiki.povray.org/content/Documentation:Tutorial_Section_2.2#Using_Focal_Blur

Hope that it's useful to you.
Happy POVing.
```