Saturday, November 11, 2006

Understand the Basics, the SIMPLE way

Ever felt the need to know a bit more about words like "exposure", "ISO speed", "Aperture", "Shutter Speed", but while looking for explanation got bogged down by further jargons, well, here i will try and explain what they mean, the way it should be ;-"). (I mean photography is art, not rocket science).

Consider a the task of making a dot on a paper with a sketch pen, now the size of the dot will depend on how long you keep the sketch pen in contact with the paper (shutter speed), what is the size of the tip of the pen (aperture), and also on the absorbing power of the paper (ISO speed), sum all these factors and you get the net 'exposure' that your paper had with the sketch pen.

All of these are valid for both digital and analogue cameras.
Now, in a little more detail
Aperture: Well this is measure of how much the lens opens up, to let the light in. They are represented by f numbers like f2.6, f8.0 etc. Please note, smaller the value, wider the opening. (relate to the size of the tip of the sketch pen)

Shutter Speed: This indicates the time, that the shutter (internal cover of lens) opens up to let the light reach the sensor, higher the shutter speed, smaller is the duration, lesser the light that reaches the sensor (relate to the time of contact of sketch pen and paper)

ISO Speed: This term relates to the sensor (film in case of analogue cameras), higher the speed, less light is needed by the sensor to see the object. Typical speeds are ISO 80, 100, 200, 400 800 and so on.

Exposure is the sum total of all these, by that i mean, it is the net amount of light that falls on the sensor/film.

I will explain each of them in more detail also, in future posts, keep checking.


p.s: These are not very exact and extremely technical definition, because their purpose is to explain to beginners and to people who don't have any idea of what these terms mean, but yeah, they are decently accurate to start with and simple enough to understand.