Fotografi: Belajar term baru. HSS & Forced Perpective.
Minggu ni, saya belajar 3 perkataan baru dalam bidang fotografi.
HSS & Forced Perpective.
Perkataan Pertama: HSS
Bermula dengan rakan saya E, nyatakan kesukaran melaksanakan fill-in flash waktu tengahari.Saya tidak ada pengalaman sedemikian. Setahu saya, saya buat okayyy.. aja. Lepas gali sesikit, barulah saya perasan, yap, adakalanya, latar belakang saya agak over exposed bila saya buat fill in flash.
HSS tu apa?
Dari wikipedia:
Focal plane shutter synchronization
Electronic flash units have compatibility issues with focal plane shutters. Focal plane shutters expose using two curtains that cross the sensor. The first one opens and then the second curtain follows it after a delay equal to the nominal shutter speed. A typical modern focal plane shutter takes about 1/200s to cross the sensor, so at speeds shorter than this only part of the sensor is uncovered at any one time. Electronic flash can have durations as short as 50 µs, so at speeds above the shutter traverse time only part of the sensor is exposed. This limits the shutter speed to about 1/200s when using flash.
High-end flash units address this problem by offering a mode, typically called FP sync or HSS (High Speed Sync), which fires the flash tube multiple times during the time the slit traverses the sensor. Such units require communication with the camera and are thus dedicated to a particular camera make. The multiple flashes result in a significant decrease in guide number, since each is only a part of the total flash power, but it's all that illuminates any particular part of the sensor. In general, if s is the shutter speed, and t is the shutter traverse time, the guide number reduces by √s / t. For example, if the guide number is 100, and the shutter traverse time is 5 ms (a shutter speed of 1/200s), and the shutter speed is set to 1/2000s (0.5 ms), the guide number reduces by a factor of √0.5 / 5, or about 3.16, so the resultant guide number at this speed would be about 32.
In fact, current (2010) flash units frequently have much lower guide numbers in HSS mode than in normal modes, even at speeds below the shutter traverse time. For example, the Mecablitz 58 AF-1 digital flash unit has a guide number of 58 in normal operation, but only 20 in HSS mode, even at low speeds.
Faham? Tak? Dah agak dah. Hahaha!
Ok, secara simplenya nak hasilkan gambar begini:
Apa susah, on Flash, ambik ajalah, kan? Malangnya, untuk ambil gambar sebegini, anda perlukan Flash yang support HSS. (High Speed Sync). Malangnya Nissin Di466 dan Nissin Di622 saya, dua-dua tak support! hahaha. Dalam contoh gambar di atas:
Shutter: 1/1250
f/stop: f/2.8
Nissin saya sync pada kadar 1/200 sahaja, bermaksud, kalaulah saya yang mengambil gambar di atas tu, gambar awek tu akan maintain cun, tapi backgroudnya, akan over exposee.... langit takkan secantik gambar ni. Huhu...
Solution:
1. Adjust composition/model, supaya anda tak perlu guna fill in flash. (Sun shining on your subject shoulder would be a good rule).
2. Bracketkan. Ambil 2 exposure. 1 for the sky. Another for the subject. Later adjust dalam post processing software. Tapi model anda kena statiklah kejap.
3. Tunggu petang sikit lah atau mendung... tu pun nasib! hahaha!
Moral of the story, Bila beli external flash unit, kalau ada duit, beli Canon yang support HSS. Kalau tak cukup duit... boleh beli Nissin tapi anda kena faham limitasinya. Kan? Masa saya beli dulu, sumpah saya tak tau menahu pasal HSS ni. Kalau saya tauuuu.... saya beli nissin juga, sebab bajet tak ada! hahaha!
Perkataan Kedua: Forced Perspective Photography
Dari wikipedia:
Forced perspective is a technique that employs optical illusion to make an object appear farther away, closer, larger or smaller than it actually is. It is used primarily in photography, filmmaking and architecture. It manipulates human visual perception through the use of scaled objects and the correlation between them and the vantage point of the spectator or camera.
Again, faham tak? hahaha... nilah kata orang, a picture worth a thousand words.
Nilah maksud dia:
OOOOOooooooo... tu ka? Dah lama tau! kan? Cuma tak tahu term dia aja! hahaha! Go ahead! Amazes yourself! Google around google images using term Forced Perspective. Memang menarik! Boleh bagi anda idea macam macam nanti! Best of all, pakai kamera phone pun boleh.. hehe.
Layan bukansepet, layan.
p/s:Kata 3 perkataan. Mana lagi satu? Haha.
Perkataan Ketiga: belajar: Canon 600D.
huhu... nangisss...
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