[mIkEnG]

如果用Sigma 70-300mm F4-5.6 APO Macro Super II想加個2X extender可以用邊個呢?價錢如何?

同埋用左extender除左入光量仲會影響d咩呢

for canon

thz

[焦急無力]

Extender will affects the image quality firstly . Second,the aperture will drops 1 stop(i.e.f/8 ) if U're using the above Sigma len with a 1.4x extender,and 2 stops with a 2x extender.The bigger the x,the worse optic quality may be obtained even U use Canon or Sigma extender.If U really want a extender, I will recommend U to use Sigma 1.4x extender( because of lower price with satisfactory performance & optic quality )
Price : http://www.ygdragon.net/index.php?page=photo/cameraprice.htm

[mIkEnG]

但係sigma suitable lens list好似冇
http://www.sigma-photo.com/lenses/lenses_all.asp

會唔會用唔到?