[AhBern]

Hi C Hings,

What is the differenec between 1.4x/2x extender and extension tube?

Thanks,
AhBern

[Obi-Wan]

extender 1.4 or 2x for convert some Canon lens to 1.4 or double its focal length, with 1 stop or 2 step lost in light for shooting (most likely) distant objects.

extension tube does not have lens elements, it only increase the distance between the lens and the sensor or film, used to shoot macro. BUT since the distance from sensor to lens is increased, the loss in light increases as the distance increases, also the defect in the lens, sharpness etc. also decreases

[calwkf]

兩種都唔同野黎既, 可以比較既咩？

Extender 係增距環, 故名思議係把鏡本身既焦距增加, 1.4x & 2x 好明顯係佢地增加既倍數, 但相對光圈也會相對增加, 1.4x 加一級, 2x 加兩級.

Extension Tube 係微距環, 係用黎把鏡既可對焦距離縮短, 但相對也會有失光情況.

[AhBern]

Thanks for the help from both of you!

Another question, if I add a 1.4 extender to a F2.8 lens, the biggest Apeture and Auto Focus function will be affected, right?

[Obi-Wan]

The Canon 1.4X & 2X are specific for some lens only because the front element of the extender can block the rear element of the lens. For a f2.8 lens, the effective f stop will be f4 (if u are using the original canon lens, the camera will show it as f4, but if u some 3rd party lens or converter, the camera will show it as f2.8 (but the light intensity is the same as f4)

Autofocus will not be affected if the lens is f4, f2.8 etc., that is u can still use the central sensor to autofocus.

[AhBern]

Hi Obi-wan,
Thank you so much for your advice! It's greatly helpful!

Cheers,
AhBern