26 Feb 2011

1am in Sri Lanka



Funny thing is, it was not 1am, but 10pm. Regardless, it was night, and the theme this week at WDYL is Night Shots.
So in the spirit of sharing, I'm going to share a little I know about ISO, because I hate flash (well the kind I have built into my little Canon 450d, anyway).

We know that the camera is less sensitive to light than the human eye, and so we have to help it out. To get the most light out of the situation, we can lower the shutterspeed, raise the aperture (F-stop), and we can also increase the ISO.

ISO stands for "International Organization for Standardaisation" and there is a great definition on Wiki Answers here. Basically, the sensor (which has replaced film in modern cameras), is made up of lots of tiny crystals. From what I can gather, If you set it at a small ISO, you have the smaller crystals taking in the light. If you set it at a higher ISO, the larger crystals take in the light. Because the larger ones can absorb light faster than the small ones, it allows us to keep the shutter speed or aperture higher - very handy if you don't have a tripod.

However.

Making the sensor more sensitive to light also makes it more sensitive to noise - the tiny particles that can especially be noticed in the darker portions of the photograph. In the photograph above, this can be seen, and rightly so - I took it at 1600ISO, which is as high as my camera goes. But I think the graininess in this instance works very well, and fits with the old and gritty nature of this bedraggled timepiece.

What do you think?