Understanding Photography Term

With the advance of the technology, photography gear is getting cheaper and affordable. I believe most of us will at least have a Digital Camera and Camera phone.

Have you even wonder how a photo is taken? The concept is simple – Record the moment of light ^_^, some say that photography itself is to “capturing light and shadow”

So, how does we capture light and shadow then?

Introducing the Exposure Triangle:

ISO,Aperture and Shutter speed.

ISO

What is ISO?

Before the time of digital age, photographer use Film to record photo, and those film have a rating of ISO100/ISO400.

Those number indicate the film sensitivity to light, The higher the number the more sensitive the film to light.

In digital age, the ISO is set in the Photo sensor itself, but increase the voltage of sensor, it can became more sensitive to light. However, this method have a huge drawback. More voltage to the sensor also make the sensor produce more noise.

Here some example of the different ISO setting in normal Digital camera (taken from www.dpreview.com)

As you can see, the higher the ISO setting in Digital camera, the noise will occur and it ruin the picture. The lower the ISO, the smoother the photo

For current digital camera (compact, not DSLR) in the market, ISO 400 seem to be the maximum ISO that give acceptable result. For LX3 owner, ISO 800 is still acceptable ^_^

So, when we going use what ISO setting when taking photo? WELL, you need to take the other 2 element in mind too, the aperture and shutter speed.

Aperture

Aperture, in short, mean the amount of light that the camera allow to reach the sensor/film.

Aperture is listed in terms of F-numbers.

the bigger the value of the F number, mean the hole is small and less light is coming through.

Here the sample of Aperture size:

The bigger the aperture open, more light coming through but you lose overall focus range.

The BOKEH effect or Depth of Field (DOF) effect – The close object get the focus while far object became blur can be achieve by using Big Aperture open (Low F number / F1.4) and low focal length (Zoom all the way out).

Shutter Speed

Shutter speed is how much time the camera open the Aperture (the window/hole) to let the light in.

The more time the shutter is open, more light is coming in. Think the shutter as a water hose, the longer you keep the water hose open, the more water you have.

The usual shutter speed range from 1/1000 sec to 8 sec for normal Digital Camera.

LX3 shutter speed range from 1/2000 sec (blazing fast ^_^) to 60 sec (can take the galaxy d)

When go below 1/30 sec, most people have problem holding their digital camera steadily and thus result in some shaking photo.

The trick to calculate a safe shutter speed (the lowest shutter normal people can hold) is the 1/focus length of the camera.

For instance, if you using 28mm focus length (the widest zoom in most camera), the safe shutter should be around 1/30 sec.

For camera with super zoom like 300mm focus length (10x zoom in most camera), the safe shutter should be around 1/300 sec.

Use tripod or put the camera in stationary place if you intend to go slower that the safe shutter speed.

Another way to reduce the handshake while taking photo is the posture you handling the camera. Hold the camera steadily with a L-shape hand at the camera bottom and hold your breath until you have done pressing the shutter release button. Else, use the burst shot feature in some camera to rapidly take 2 or 3 picture in rapid time and pick the one that less blurring ^_^

Conclusion

How does ISO/Aperture/Shutter speed affect each other? There are much more complicated and detail explanation over here –> http://www.uscoles.com/fstop.htm but i would like to sum it out for beginner ^_^

Let look at one scenario:

Let say we want to record a photo with the 1 unit of exposure (the total light that get capture)

We can use 1 unit of ISO (ISO 100) X 1 unit of Aperture F-stop (F2.8) X 1 unit of Shutter Speed (1 sec) = ( 1 x 1 x 1 ) = 1 Unit of Exposure

We can also achieved this using different setup:

2 unit of ISO (ISO 200) x 2 unit of Aperture F-stop (F 2.0) x 1/4 unit of Shutter Speed (0.25 sec) = 1 unit of Exposure

As you can see, there are many combination you can choose when taking a photo. Of coz, different setup is suitable to use in different scenario, for example, the setup #1 give you clearer and less noisy picture because of the lower ISO setting. The example #2 however suitable to use in dark place where you need to capture as much light in very short time (Fast shutter speed) to reduce shaking picture ^_^

LX3 have very wide open (photography term – Fast) Aperture which is F2.0 thus it is possible to get good result in dim light environment without need to push the ISO setting much higher or slower shutter speed which might result in shaking and noisy picture.

Side note for the usual setting i use with my LX3:

Bright sun light (clear sky)

– ISO 80-100 , F5-F8, Shutter speed range from 1/1000 to 1/60 sec

Daylight (cloudy)

- ISO 100-200, F2.8-F5, shutter speed range from 1/250 to 1/25 sec

Indoor (with bright light)

- ISO 100-400, F2.0-F5, shutter speed range from 1/125 to 1/25 sec

Indoor (with dim light)

- ISO 400-800, F2.0-F2.8, shutter speed range from 1/30 to 1/15 sec

Dark place

- Luck if use only hand held.

- Use tripod or put the camera in stationary place and use self timer to capture the photo without shaking the camera. (most of time shutter speed is > 1/10 sec)