[joeybc80]

我有支70-200MMM...但覺得焦距唔夠...請問C-HING們呢兩支點選擇呢???
100-400F4.5-5.6 / 300F4...THX

[Obi-Wan]

300/4L IS of course

[joeybc80]

但係300MM加1.4X = 420MM ; 100-400MM加1.4X = 140MM-560MM...焦距上唔係好似滿足D???...THX...

[rankinelo]

joeybc80 CHing.

if you use 100-400MM加1.4X = 140MM-560MM, then it is probably that you won't hv AF unless u use 1 series...

in addition, I also think that the PQ for 300/4L is superior (even with 1.4x)... furthermore, 300MM加1.4X = 420MM has AF for all EOS bodies...

[joeybc80]

C-hing...Why it have not AF on the 100-400 + 1.4X ?... Thx...

[sannaso]

因為大白加左1.4就減左一級光圈,除1仔外其他機都會無左AF

[Obi-Wan]

Canon set 左係非1 series機身不能在光圈值大過5.6時AF

其它body,
用膠紙黐住鏡向extender左三點金手指，夠光時AF可用