[Cepa]

大光圈可以在傳統菲箖相機做出淺景深效果，但係應用係數瑪相機，又是否有同樣效果？我見到有些數碼相機宣傳，標榜有大光圈值。咁F1.8與F2.8 做出淺景深效果，又是否分別很大？

[jammy_2002i]

你知唔知道光圈大細除左會影響景深之外仲會影響快門速度?

[tam_dominic]

Large aperture is important
because
large aperture allows more light goes onto the sensor
thus
enables you to use higher shutter speed
results in
freezing motion of object and
avoid blur image due to camera shake.

Happy shooting !

[mrskyhook]

except the difference of background distance and the object distance is very large, like the case of macro shooting, the deep of field is not likely possible in non-DSLR DC because the sensor size is too small.

But big aperture (fast lens) can shorten the time of exposure, so very useful such as freezing an action and avoid hand shaking!

[jammy_2002i]

係時候要溫下書~

http://www.dcfever.com/glossary/glossary.php?glossaryID=1

[gaiuswong]

景深深淺響DC真係分別唔會太過明顯,做唔到淺景深亦是DC既弱項之一,因一般DC 既CCD size比 DSLR或菲林相機細好多,有大光圈值景深固然可以淺D,但都要配合埋鏡頭既焦距,例如你用一支如200mm~300mm長焦距鏡頭再配合大光圈值可以好輕易得到重立体感個人凸哂出黎果種淺景深效果,但如果你用一支短焦距廣角鏡頭,就算支鏡有大光圈值都做唔到重立体感個人凸哂出黎果種淺景深效果.

[cable711]

經驗淺談：

在prosumer級相機中，在8X zoom、高快門、大光圈，所做出的bokeh效果遠遠不及一支50mm在dslr上比較，說牙纖與竹竿的比較。可以解釋為不同ccd 的size作出數字上的差距，再深入的計算方程式，需有勞較高層次的板代答。

[jammy_2002i]

要o係prosumer級相機中(例如FZ-10)，用到12X zoom以上、2.8光圈,景深點都唔會太明顯,反而會令到色散問題出現而引致畫質下降, 所以想o係dc做到淺景深人像照片都係算吧啦...面對現實,否則冇人會買dslr!

[mrskyhook]

for ur info:

http://dfleming.ameranet.com/dofjs.html

it's a very good web page to calculate the deep of field and u can see the relation of the factors affecting the DOF.

and u can calculate the so-called "snap-shot" focus (Hyperfocal distance). so for the DC with custom mode, (eg A80), set the focus to the "Hyperfocal distance" to obtain the biggest deep of field.