HD source to work in Nuke & Boujou(setting up the focal length of the lens)

[kevin_jeoung]

Hello,

This is Kevin, and this is my first post here in VFXtalk

I have some problems about setting of Nuke when working with HD sources.

I believe that the lens of HD cam differs from the one from film cam,

and I don’t have any idea on how to adjust the proper ‘focal length’ .

First of all, I would like to know how they are different from each other.

Second of all, I would like to find the good way of calculation between the focal length of

HD and Film camera(35mm), and how to apply it into the software like Boujou, and Nuke.


I would like to know the fundamental reason, and I think it has to do something with the

size of CCD. Anybody who have done this, please give me a good solution.

Thanks

[milkey]

this is not a direct answer... Computers understand lenses and cameras as Field of View expressed in degrees. All those focal length values are a conversion from FOV to focal length calculated like this:

0.5*PW/TAN(0.5*FOV/57.296)

its read: half of plate width divided by tangent of half the FOV divided by 57.296 => focal Length.

Conclusion: Plate width is necessary to interpret FOV as focal length. Nuke has settings for plate width also Boujou. Once you get the correct plate width the software will display real world focal lengths similar to the lenses the plate was shot.

Regards Adrian C