A little confused

[Tighearnach]

Hello.

I am just trying to get something clear in my head.

I have a 300mm lens and im thinking of buying a 1.4X converter. I use a cropped sensor camera (400D).

So am i right in saying that i will have a magnification of 420mm but my field of view (if thats what i shud call it?) will be 672mm or thereabouts? Or am i way off here....?

Thanks again
T

 

[Shibby!]

You sir, are correct..

In equal's to full frame focal lengths, you will have 672 mm of zoom, however, put that on a full frame digital camera, and you'll be back at 420mm with the 1.4 TC.

 

[Happy Hour]

don't forget you almost double you F stop with a tele converter.I use my 2x all the time but on a 300mm lens full zoom its at a f11 as the widest aperture i can go.

 

[Helen B]

don't forget you almost double you F stop with a tele converter.I use my 2x all the time but on a 300mm lens full zoom its at a f11 as the widest aperture i can go.

The F-number gets multiplied by the same factor as the focal length, so a 1.4x teleconverter results in a one-stop increase in the F-number (eg f/4 to f/5.6) and a 2x teleconverter results in a doubling of the F-number, or a two-stop increase in F-number. This only applies to the type used behind the main lens. Teleconverters used in front of the main lens should not affect the F-number.

Best,
Helen