Common Metering

Hi my friends, I am back again. This time I wanted to write something about the common metering used. I have wanted to take a shot of a room without any light but just with a lit candle for some time. :) And my time has come, 2 days ago on Xmas eve, at around 7.45pm, TNB (Tenaga Nasional Berhad - the electricity company in Malaysia) decided to give us a great dark Xmas eve, so my whole house and the neighbouring houses were in total darkness. My grand mother lit a few candles, and she has also passed me one for my room. I took this opportunity and tried out the 2 metering features : Evaluative and Spot, just to show what I have learnt.

Evaluative metering basically is an assessment of the exposure of the whole surrounding that your camera has in scope, it is calculating an AVERAGE exposure of the scene. The candle light is bright by itself and that requires limited exposure hence faster shuttle speed (with constant F3.5 and ISO100), while the surrounding scene is dark. An average evaluation will give longer exposure time (slower shutter speed), and a little overly exposed candle light.

Spot metering assess the exposure required for a particular spot in focus, so when I focused on the candle light itself, since it was bright enough, it did not need long exposure time, hence a very well exposed candle light, but of course, darker surrounding.

Lets take a look at 2 sets of comparison of the below :-

Spot Metering - F3.5, ISO100, 1/3 secs (well exposed candle light)

Evaluative Metering - F3.5, ISO100, 1/2 secs (A little over exposed candle light)

Spot Metering - F3.5, ISO100, 1/30 secs (well exposed candle light)

Evaluative Metering - F3.5, ISO100, 1/10 secs (A little over exposed candle light)

Hope this helps to shed some light to someone that is as new as me, who is just starting to learn more about photography principles. :)

Gotta go now, am enjoying a glass of ice blended coffee at Coffee Bean (R). Merry Xmas & Happy New Year! :)