Canon 2x extender

[harrys]

Can anyone please tel me what a 2x extender lense do , reason why I ask, a friend of my FIL told him that when you use a 2x extender lense on his 300 mm lense it will be like a 600mm lense

[Dewi]

Hi Harrys,

a 2x convertor doubles the focal length of the lens, so you are corrrect, but do not confuse them with extension tubes which are for using the the lens for macro photography.

Check compatibility with the lens as they will not autofocus with some lenses, or even not fit if it's not an own brand lens. You will loose quality in the image, unless you go for the high end newer versions. You will also loose 2 stops with it attached, i.e. an f4 lens becomes f8.

I use a Nikon one. Most of my KTP pics were with a 300mm and 2x convertor attached.