Nikon 18-200 mm VR not reaching 200 mm focal length

I just got the VR 18-200 mm. When doing some initial testing I noticed that set to 200 mm it has the same coverage as my Nikon 70-300 mm set to 130 mm.

The test was done at a relatively short distance – about 2 meters.

Has anyone else noticed this? Is my lens broken? Should I take it back?

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One response:

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This is normal

There's nothing wrong with your lens. It is sometimes called “focus breathing” and results from the lens' design.

Nikon 18-200 mm VR has a so-called “internal focus” (IF) design. This means that it will only have the FOV associated with a focal length of 200 mm at the long end when the focus is set to infinity. Focused at 2 meters its FOV will correspond to the FOV of a much shorter focal length, typically 130 mm, as you have observed.

If you test your lens with the focus set to infinity, I am sure that you find that at 200 mm, it will give the same framing as the Nikkor 70-300 mm at 200 mm.

Also note that the formal definition of a lens' focal length says that it is the distance from the lens' rear nodal point to the image plane when the lens is focused at infinity. While the FOV at other distances may be different from the lens' FOV at infinity, this does not change the lens' focal length.

See also this posting on CameraLabs.com by jeremy1302.

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