新手玩相機, 請大大指教

想問f2.0 可否做到下圖的效果呢 ?!  (下圖借"攝影入門"網站)

因為我每次都要zoom到好埋先有景深呢個效果 ... (幾乎是zoom 到下圖model的頭, 但取全身景, 景深總是不足)


相機____model_____________________________________景

p.s. 我的機是lx-5

望大大指點迷津!

for such photos u better have a DSLR of any kind (even NEX-5, GF1, EPL1...) then your LX5.

BECAUSE the matter is the size of the senor. not just Aperture matter, even u have F1.4 COMPACT camera and still won't get it.

IMO this photo was using something like 50mm F1.8 lens (cost u only $800-$1000) and DSLR BODY u can get an in-expansive one for only around $3000-4000 (second hand is even cheaper)

I always thought the depth of field has to do more with the focus length of the lens and the aperture. Didn't know the size of the senor matter too. Than again, I never have a DSLR. I got the concern while back when I was using 35mm film and digitial camera was just come out to the market. I guess I needed to get updated.

最重要係焦距,你用DC,做唔到咁既效果
你既情形應該係景深足過你想要既,唔夠淺
買單反吧!!

I think anyone with some knowledge on photography knows DOF ( depth of field ) is subject to 2 factors, Lens aperture and the focal length (also take into consideration is the location of your subject).  If the size of image sensor will affect the DOF, using DSLR will have NO meaning AT ALL, as what you see inside the viewfinder may not be the same appeared on the picture!

Correct me if I'm wrong, 樓主's LX-5 have a fixed f2.0, 3.8x zoom lens, that means despite the aperture setting (f2.0..f.5.6...f16...), the lens is always at it's real f.2 aperture, the only way to change the DOF is to change the focal length (zooming) or adjust the distant between the camera and the subject.

Using a lens with real aperture settings will provide more flexibility on the DOF effects, no matter you are using DSLR or not!

上次你又話系有關既,呢次又話冇關
http://www.hkml.net/Discuz/viewt ... ight=&page=8###

老老實實, 我用DC如果想做到這種淺景深效果, 有無補品可買?
或者說, 有無長焦距鏡頭可加落DC仔的鏡頭上?

冇....用ps後製吧~~
長焦鏡比dc仔係有,不過...
以前有用整左個深景深adaptor比video cam用...原理係用一支大光圈單反鏡加個盒,後面有塊對焦屏,個cam就對住個對無屏上面個影象番拍....先有單反咁既淺景深...

謝謝各位師兄, 小弟都係岩岩先離開auto 行列個幾月.. 好多野仲摸索緊 @_@

買lx5果陣, 個SALES同我講, "lx5 有f2.0 既光圈, 好易做到景深效果",   點知番到去, 個"效果" 同我之前買果部sony w10 差唔多...

可能是小弟唔多識set la , 又可能是我理解錯個SALES"好易" 既意思.. ~~

[ 本帖最後由 好平 於 2010-12-5 09:50 PM 編輯 ]

影相掂就唔洗係果度做sells啦....

比起普遍既薄裝數碼輕便機,的確係"易d"做到"淺dd"景深既效果,但應該吾係你想要果種...

師兄...我映咁耐相...大光圈果陣都未試過可以係 viewfinder 見到映出黎既景深...
你用咩相機可以係 viewfinder 睇到映出黎個景深?!?! 指點下好...

仲有呢點解我用部 40D 同 5DII 同一焦段...同一光圈...映出黎個景深都唔一樣既...
LX3 同 5DII 比都有呢個情況...究竟點解呢...
焦段同光圈都一樣咧...景深差九里遠....會唔會係唔同牌子既關係呢...

Sensor size 同 DOF 的確無關, 但個 sensor size 會影響到個 focus length, 轉左數碼攝影後, 因好多鏡頭可以互換, 而裝到相機的鏡頭標示焦距未必對應番個 sensor size, 即同一支鏡裝去兩部相機, 如果個 sensor size 唔同, 就會產生兩個不同焦距, 在同一級光圈下, DOF 就會唔同, 我意思系咁, 如果你無誤會就系我講得唔清楚

nono, 同一支鏡,裝係3/4. aps, ff 景深都是一樣的

應該係相同既視角,係唔同system先會有唔同既景深
for example:

50mm on 3/4 與100mm on FF.....水平視角幾乎一樣,影出黎左右睇到既事物都差不多,不過焦距卻相差一倍,景深都會唔同...
所以一般用家都會覺得,用FF會比用3/4更易影出淺景深

同一支鏡裝係唔同system係會得different angle of view, but not the depth of field...

既然你影相咁耐, 你應知道 SLR點解要將光圈開到最大取景, 而全開光圈取景/測光亦為一大賣點, All in all, SLR 既設計目的就系取景同拍攝都用同一支鏡頭, 亦正系呢個原因, 取景見到既就系最後拍攝到既, 用 Windows 既 terms 就系 WYSIWYG!  要系Viewfinder 睇到實際景深, 請按一按鈕將光圈 stop-down 到所選光圈數值, 大部份 SLR 都有此設備, DSLR 我用不多, 不過我相信設計應該一樣, 如果無既話, 用 LCD display 睇都系一樣!

如果你部 40D 同 5DII 個 image sensor size 系一樣既話, 理論上 DOF 應該系一樣, 但系如果你講影出黎個表現, 咁除左以上講既, 個 image senor 既質素都會有關, 相對以前影菲林, 大家可以用同一種菲林,同一種沖印, 依家既情況可以好復雜

我相信個 Sales 又無講錯既, 只系無機會好深入解釋! 所謂景深效果, 我唔知你會點理解, 景深就系景物既清晰範圍, 可長可短!  一般理解, 焦距短, 景深長, 反之亦然, 而光圈大亦能做成短景深, 小光圈就會將景深拉長, 焦距與光圈互相關連!

因為景深系光學上既表現, 所以如果你部相機光並非有真光圈調節,而系電子數值轉變, 正如你部 LX-5 physical 光圈永遠系f2, 你只能通過改變焦距控制景深,選擇就會少左, 如果我無理解錯既話!

Angle of View 同焦距有關, 以135系統為例, 50mm 鏡頭叫 標準鏡, 其中一個原因就系佢既視角最接近人眼既視角, 一支 135系統既 50mm 鏡頭裝上 3/4, APS, 同 FF, 你話比我聽實際焦距會系幾多, FF 就當然照舊 50mm, 其他兩個. you do the maths, please!

如果你話系一樣既, 咁所有鏡頭都會系同一 DOF, 咁就真系簡單啦

50mm 用係3/4視角咪變左100mm用係FF機囉,我對上既例子已經講左,....你仲反提出相同問題....

所以我咪話:

3/4用50mm與FF機用100mm視角一樣,但景深係會唔同,因為焦距係唔同,

3/4用50mm與FF機用50mm,視角唔一樣但景深就會一樣,因為焦距係一樣

你而家明未???

Angle of View 同焦距有關 <---呢點冇錯不過你漏左一樣野,應該係:

Angel of view係同時受焦距+CCD尺寸有關

不過呢個post係講緊景深!

講番樓主既問題
LX 5點解做唔到淺景深,好簡單,睇睇LX5支鏡既實際焦距

只係5.1-19.2 mm

因為佢既ccd細(1/1.63 吋),所以視角就等同35mm format既24-90mm既視角,但景深卻只是 5.1mm至19.2mm既景深
咁短焦距既鏡頭係好難做到淺景深效果,亦引正番我上面所講,同一焦距,用係唔同system個景深係不會變...

LX5你點用都只係5.1-19.2mm既景深而已