[fsyten]

我想買支長炮 for Sports & birds !!!

1.) Canon 大白 ($12000)
2.) Sigma APO 120-400mm f/4.5-5.6 DG OS HSM ($5700)
3.) Sigma APO 150-500mm F5-6.3 DG OS HSM ($6800)

我比較傾向2 & 3...
但3最wide只有150mm.....我怕有時會唔方更 !!!
大白實在太舊款了﹗IS只有兩級，但sigma有4級。而且係推鏡，感覺很怪...

[wesleyyau]

想問ching 用咩機?

[reflexboy]

大白12000可以買到?
影sports 5.6/6.3有d不足. 大白加1.4x會係我個人o既選擇!

[Ison]

請問師兄大白加1.4x係唔係要MF?

[reflexboy]

"請問師兄大白加1.4x係唔係要MF? "

NOPE!

[fsyten]

我是用50D的
另外想問下...聽話50d的對焦點只support F5.6或以上的Lens.
咁如果我用sigma150-500，支鏡遠端會變成F6.3，咁是否只能用Manual Focus ???

大白 + 1.4x其實我都有諗過。但光圈會再收細.....
可惜我上網查唔到會收細幾多....

[reflexboy]

副廠鏡答唔到你.
如果你所指o既大白係300mm f2.8L O既話,O係加O左1.4X後就變o左420mm f4 (full frame)計! 1.4X會令鏡頭失去一級光圈．

[fsyten]

thx!!!

我指的大白係100-400mm F4.5-5.6
咁1.4x係咪會再大白的光圈收細一級﹖
增距前﹕100mm F4.5
增距後﹕140mm F5.0

增距前﹕400mm F5.6
增距後﹕640mm F6.0

我咁諗arm唔arm ???

[calwkf]

"大白 + 1.4x其實我都有諗過。但光圈會再收細.....
可惜我上網查唔到會收細幾多.... "

1.4X - 收細一級 (e.g. F4 = F5.6)
2X - 收細兩級 (e.g. F4 = F8)

APS-C AF max. support F5.6, FF AF max. support F8. if over this range, need to use MF to foucs.

[Obi-Wan]

"APS-C AF max. support F5.6, FF AF max. support F8. if over this range, need to use MF to foucs. " <====== I don't know why my 350D, 400D, 20D, 50D can use my Sigma 18-200 @200 mm 6.3 AUTOFOCUS

[MN56]

大白加1.4X，係400端會變成F8。用1系機先有AF，其他機都要MF。

[reflexboy]

sorry! 我對d鏡頭"潮語"真係好鬼out!成日以為大白係指300mm f2.8L!
如果我無記錯,canon任何大鏡o係加o左1.4x或2x後,光圈唔細過f5.6 o既話都有af.


quote ""thx!!!

我指的大白係100-400mm F4.5-5.6
咁1.4x係咪會再大白的光圈收細一級﹖
增距前﹕100mm F4.5
增距後﹕140mm F5.0

增距前﹕400mm F5.6
增距後﹕640mm F6.0

我咁諗arm唔arm ???""

更正你少少, 100-400mm F4.5-5.6 加o左1.4x後會相等一枝140-560mm f6.3-8先正確.

[fsyten]

點解sigma 18-200 @200mm F6.3還可以用AF呢﹖
canon的對焦點明明只support F5.6或以上光圈.....

[jsklee]

"canon的對焦點明明只support F5.6或以上光圈..... "

Who taught you? Have you tried? Scold him/her la!

[johnxlee]

I bought Sigma 120-400mm which is really good, but soon bought Cannon 100-400mm which turns out better. I decided to let 120-400mm go (http://www.dcfever.com/trading/view.php?itemID=309122).

Cannon 100-400mm, better lense, light, but very expensive
Sigma 120-400mm , very good lense, heavier, cheaper
Sigma 150-500mm, xxxxxx, very hearvier, and not that cheap.

I think you may make a decision based on your budget, convenience and the quality. If you do care about money, definitely go with Canon 100-400mm; if you have limited budget but want a good lense, go with Sigma 120-400mm; if you have some more beduget and don't care about weight, go with Sigma 150-500mm. I warn you - the third one is really heavy and, of course, not really "portable".