[leepatrick]

張相唔清, 可能係支鏡唔夠 SHARP, 係咪？
咁你地點知道佢係真係走焦 or 只係唔夠 SHARP??
2 者有咩分別？

我本身有原廠 350d kit lens 同 sigma 鏡
全部都可以正常對得到焦, 咁係咪代表我無事呢？

[雞能]

我支sigma長焦都冇特別test過,
映出黎sharp就收貨...

我好懶...

[man1492]

"張相唔清, 可能係支鏡唔夠 SHARP, 係咪？"

No. Sometimes very sharp, sometimes doesn't, for the same scenary with the same settings.

[leepatrick]

你果支係 80-400 or 50-500 ?

我就係用緊 80-400 喇~

[beancurdbean]

唔Sharp --> 全都唔sharp
走焦 --> 其他地方sharp過你想中焦的地方

[leepatrick]

但如 wide 鏡, 一向成像唔會太高, right?
咁 wide 鏡唔會 sharp 我會接受,
但另一方面會唔會又係你地講既走焦問題呢？

[leepatrick]

走焦 --> 其他地方sharp過你想中焦的地方

?!?!? 咁又真係無試過喎,
我一直以為...走焦係指 :

有一件東西距離你 50 cm, 你以佢對焦, 如佢表示成功對焦,
應是用了 50cm 去對焦, 但走焦的話, 可能機身錯用了 51 or 49cm 去跟該東西對焦, 但一樣表示成功對焦...所以影出黎 d 相在 pc 睇番就全部都對唔岩 focus.... (原來唔係咁咩？)

[beancurdbean]

你無錯
如果走焦在51cm, 所有物件在51cm就會清過50cm你想中焦的物件

[andy3210]

leepatrick

你無錯, 只不過應該 51cm / 49cm 既野會 Sharp.

[beancurdbean]

不過仲要考慮景深
如果景深有10cm, 走焦5cm都唔會有問題

[dslrfever]

One of the cause may be resulted from:

Focus Lock and Re-composite (aspecially with large aperture).....

EOS Manual noted that we should composite and select the focus point, then shot....

[eng3118]

我仲係分吾到咩係走焦 ....
究竟係
1. 焦距吾準
定係 2. 焦點位置吾準

我好混亂ar !

[beancurdbean]

Wrong AF is 1;
Back / forward AF is 2;
1 & 2 are out focus