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Questions tagged [focal-length]

Focal length is the distance (measured in mm) between the surface of a lens and the focal point, when the lens is focussed at infinity. Smaller focal lengths indicate wide-angle lenses, larger focal lengths indicate a telephoto lens.

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What does the focal length of a fisheye lens mean?

Say an ordinary lens, Sigma 30mm f1.4 for example, is designed for APS-C and thus produces images that have a 35mm-equivalence of 48mm. But what about the fisheye ...
Amarth Gûl's user avatar
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Motion tracking/VFX: How to get needed info for iPhone camera?

Basically, I want to do VFX with my iPhone SE 2nd Generation front-facing camera. The software being used is Blender up-to-date. I'm not sure what to set Blender for in the track camera settings field,...
TheLabCat's user avatar
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Measure the area of an object in an image by using fx and fy and given distance (distance between camera and object pixel-wise)

I want to measure the area of an object in an image. I have fx and fy of the camera and also since I am using depth camera I have the distance between camera and the object pixel-wise. Could you ...
code_lover's user avatar
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Is this effect because of the lenses? what type?

https://www.instagram.com/p/CwsKDthOdST So in this video, the legs of the man look really small. I thought at first it must be because of the lenses but if it were for wide angle lenses, that would ...
jazmin garcia's user avatar
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I want to measure far distance focus in a short space, but give myself a greater FOV, how would I do that?

Building off of this question, say I put a 1 m lens in front of a camera so I can see a virtual image at 500 m to focus to, when I place an object within the focal length (0.998 m), but I want a ...
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Is it possible to calculate field of view and aperture given focal length, k1 and k2?

I have some data coming from an API that looks like this: "camera_parameters": [0.785028, 0.032519, -0.053622] and the data structure that I would like to ...
M.Ionut's user avatar