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zainzubir
15th April 2008, 01:11 PM
Digital Photography Tutorial – Spot Metering
Author Cliff Smith
Published 13th Apr 2008

Back in the "good" old days, most cameras had very crude light meters, if they had light meters at all. I remember owning a Russian Zenit-E 35mm SLR camera in the 1970s that had a simple selenium photocell mounted outside the camera on the front of the pentaprism, with a moving needle in the viewfinder but no actual link to the exposure controls, which were fully manual. It was a light meter of sorts, but it was a bit hit-or-miss and would be utterly defeated by shooting into the sun or other bright lights. The only way to get a good photo out of it was to take a light reading and then guess. It was certainly more of an art than a science.

http://www.trustedreviews.com/images/article/inline/7314-ZenitE.jpg

These days things are very different. Even the cheapest digital cameras offer sophisticated metering systems featuring through-the-lens centre-weighted metering, multi-zone evaluative metering, and even spot metering. There should really be no excuse for a badly-exposed photograph anymore, but the trouble is that most people don't know how to make the best use of these advanced features, and usually just leave their cameras set on the default multi-zone mode. Let's see if we can't do something about that, by explaining how to use least-understood but most creatively useful of these features, spot metering.
http://www.trustedreviews.com/images/article/inline/7314-CompactBack.jpg

You'll find spot metering either in your camera menu under Metering Mode. It usually appears alongside Evaluative (multi-zone) and Centre-Weighted, and is identified by an icon of a rectangular box with a round dot in the middle. On some DSLR camera metering mode will have its own external control, while on many compact cameras it is found in the function menu.
http://www.trustedreviews.com/images/article/inline/7314-K20Dspot.jpg

The way spot metering works is pretty simple. Rather than measuring the light level across the whole scene, spot metering only takes a measurement from a small spot in the centre of the frame, typically an angle of only about one or two degrees from the centre-line of the lens. Since it ignores everything outside this area it is a very useful tool for coping with unusual lighting conditions, such as very strong backlighting when shooting into the sun or against a brightly lit window, or shooting light objects against a dark background such as a band on a stage.

The photo below was taken using standard multi-zone evaluative metering. As you can see the brightly lit background has caused the forground to be under-exposed.

http://www.trustedreviews.com/images/article/inline/7314-AstonMultiZone.jpg

By using spot metering the background is ignored, and the front of the car is correctly exposed. The spot meter measures the light in approximately the area of the red circle.

http://www.trustedreviews.com/images/article/inline/7314-AstonSpot.jpg

Spot metering is best used in conjunction with another little-used camera function, auto exposure lock (usually abbreviated AEL), and also with exposure compensation. To understand how best to use it, a basic understanding of how camera light meters calculate exposure will be helpful. I've written a tutorial on this subject which you can find here, but the most important part is the explanation of the zone exposure system.

http://www.trustedreviews.com/images/article/inline/7314-LockButton.jpg

On some more advanced cameras, exposure lock will have a separate control, often a button near the shutter release. On most compact cameras, half-pressing the shutter button takes a light reading which is held until the button is released or the picture is taken, however be aware that in many cases doing this will also hold the focus as well. On some cameras it is possible to make a change in the set-up menu so that holding the shutter button will only lock exposure.

The way to use this combination of features is to select the area of your picture from which you wish to take your light meter reading, centre this area in the viewfinder and half-press the shutter. Either press your AEL button to lock the exposure or hold the shutter button while re-framing the shot, then press the shutter release button fully to take your picture. On some cameras AEL holds the exposure until pressed again, on some it holds for a pre-set duration of several seconds, while on others it holds until the shutter button is fully pressed. On some DSLRs the operation of the AEL control can be customised via the set-up menu. Look it up in your camera's manual to find out how yours operates.

For portrait shots, it's usually best to take a spot meter reading from your subject's face, since this will normally be the main focus of the picture. For people with average south-Asian or lighter Afro-Caribbean skin tones, no further adjustment is necessary. For typical Caucasian skin tones, add one stop of exposure compensation (+1), while for subjects with darker Afro-Caribbean skin tones, subtract one stop of exposure compensation (-1).

A useful accessory often used by professional photographers for making accurate spot meter exposures is the grey card. If you read the exposure tutorial I linked earlier, you'll have seen the chart of the zone exposure system. A grey card is literally that; a piece of card coloured mid-tone 18% grey, and you can buy them at any good camera store. Lastolite makes a particularly good one that folds up to pocket size and has a white reflector on the other side.

http://www.trustedreviews.com/images/article/inline/7314-Lasto.jpg

The grey card is temporarily placed in the scene you wish to photograph, positioned so that it is under the same lighting as the subject, and a meter reading is taken from the surface of the card by pointing the spot meter at it. For portrait shots you can get your subject to hold the card while you take a light reading. Once the exposure has been set the card is removed, before the picture is taken.
http://www.trustedreviews.com/images/article/inline/7314-iStock000001740497XSmall.jpg


Some cameras, for example the current range of Olympus digital SLRs, have two extra spot metering options, highlight and shadow metering. In these modes, the meter is calibrated for zones eight and two on the zone system chart. In highlight metering mode, taking a spot meter reading from the most brightly lit parts of a scene will result in a correct exposure so that highlights are bright but with detail visible. Likewise using the shadow metering on the darker areas of the scene will produce dark shadows but with visible detail.

siurce:

http://www.trustedreviews.com/digital-c ... etering/p1 (http://www.trustedreviews.com/digital-cameras/review/2008/04/13/Digital-Photography-Tutorial-Spot-Metering/p1)

buttet
15th April 2008, 02:35 PM
yeah good infoo penerangan yang mudah difahami

zilzals
15th April 2008, 08:08 PM
mcm tu rupenye nak pakai spot metering.tq hanty:)

Ayie
16th April 2008, 11:29 PM
useful! tenkiu hanty...

qursany
21st April 2008, 09:51 AM
Tutoria yang bagus! Tetapi kalau dalam bahasa melayu aku rasa lebiiih bagus! Lebih superb kalau sample gambar sediri yang ambik! sebab kat malaysia ni kurang sangat tutorial dalam bahasa melayu. (bukan tak boleh berbahasa inggeris! tetapi Bahasa melayu memartabatkan bangsa!)Adiosssss

zainzubir
21st April 2008, 05:06 PM
since qursany boleh berbahasa Inggeris, apa kata tolong translatekan untuk kebaikan ahli lain yang tidak berapa lancar berbahasa Inggeris?? :wink:

jebonzas
30th January 2009, 11:20 AM
since qursany boleh berbahasa Inggeris, apa kata tolong translatekan untuk kebaikan ahli lain yang tidak berapa lancar berbahasa Inggeris?? :wink:

gi cit cat dot com kalau nak translate malay... tapi bahasa tunggang terbalik le.. :)

izzat3114
30th January 2009, 11:57 AM
owh baru la paham macam mana rupernya guna metering ni.. thanks.

mzabdullah
30th January 2009, 10:49 PM
Satu artikel yg menarik dan informative. Thank you kak zain for the effort. Cuma saya tanya satu soalan je (jgn marah pulak) penyiaran artikel ni ada kebenaran ke drpd Cliff Smith tu? Saya bukan apa nanti niat kita nak buat benda baik bertukar jadi problem pulak...so nanti kak zain dan FMDC pulak yg terlibat...tapi kalau mamat tu tak kisah for the sake of knolwedge-sharing alhamdulillah...

Selain drpd artikel Cliff Smith kat atas tu saya cadangkan jugak saudara-saudari lawati website mamat ni..nama dia Bahman Farzad yg memang penggemar spot metering dan nama website dia pon spotmetering.com (http://spotmetering.com/)

fahmishah
5th February 2009, 06:56 PM
350D xde spot metering.
tunggu 50D keluar

red
15th February 2009, 02:20 PM
350D xde spot metering.
tunggu 50D keluar

tu laaa.. kalau tak dulu aku nak angkat 350D gak.

adik_faber
15th February 2009, 03:12 PM
kamera lama tu mcm kamera abah la...hihi..
owh..begitukah kegunaan nye spot metering...tq for d info.
sbelum ini...ingt kan shj2 diadakn...dan tiada perbezaan nak guna mana2 spot metering itu.....

alphamann
16th February 2009, 12:11 AM
mekaseh hanty for nfo given usefull indeed

adipatigusti
16th February 2009, 10:27 AM
fahmishah quote
350D xde spot metering.
tunggu 50D keluar

takpe guna partial metering je yg ada pada 350D. Cuma keluasan kawasan tumpuan besar sikit (6.5% to 10.5%). Memadai dengan kamera yg kita ada.

Partial metering.
(Canon) Many Canon cameras can restrict metering to a small area at the centre of the viewfinder or around the current focus point. This area, typically 6.5% to 10.5% of the total image area, is too large to be a spot meter and so is called the partial metering area. This mode is indicated on cameras by the partial metering icon (http://photonotes.org/cgi-bin/entry.pl?id=|Partialmetering).

6031bhq
2nd August 2009, 08:34 PM
very helpful! thank u hanty!