Understanding – ISO
Photography is about using the available light to make a good exposure. Knowing how your digital camera can be manipulated to deliver a good exposure under all types of light situations will take you a long way to making better photographs overall.
The ISO setting on your camera is simply the film speed standard set by the International Organization of Standardization. Those with film cameras can buy rolls of film from 50 ISO and upwards that will suit certain light situations. The downside is that once you start using that roll of film, you need to expose the entire roll.
Of course the majority of people now use digital cameras, not film, which can be manipulated to handle ISO speed from 50 to now above 3200, with some amazing results in high end cameras.
You can take a few shots inside a dimly lit building, walk outside into the sunshine, adjust your ISO setting and make more photographs that you will be proud to call your own. No more waste and no more technical downsides.
What actually goes on in your camera is that a low ISO of 100 blocks light to the sensor, while a higher ISO setting allows more light to the sensor. Once you have a handle on what your ISO actually does, digital photography becomes much easier.
In Layman’s Terms – Changing the ISO number will determine how fast your camera takes the shot. Which in turn also determines if the resulting image is exposed properly i.e. is it too dark, too light, or just right.
Have you ever photographed a scenery or subject where your camera seems to have taken forever to take the shot, especially at night time or Indoors? Increasing the ISO number can help you with this problem.
Have you ever taken an image where the result is too dark or in some cases pitch black? Again, increasing the ISO number can help you with this problem as well.
No doubt by now you’ve tried to photograph a moving subject like a child running or bird flying and noticed motion movement or ghosting in your images? Again increasing the ISO number will help you shoot faster to assist in eliminating this problem.
Program mode is the easiest setting to use when learning ISO on your digital camera. Program mode is displayed via a letter P on most entry level camera brands.
Many people ask “what is the best ISO setting for my camera”. There is no answer to that question. The question that they should be asking is, “what is the best ISO setting for this particular light situation”.
To better understand your cameras ISO setting, lock yourself in a room and close all the doors and curtains so it’s darker. Set your camera to P mode and set your ISO to the lowest number it will go. For many this will be 100. Now take a shot. You should find your camera takes a long time to shoot. So long that it is impossible for you to hand hold the camera and get a good image!
Now change the ISO to the highest possible number for your camera model and take the shot again. This time notice how fast your camera Shoots!.Your should find it shot much faster than it did when your ISO was 100?
The higher the ISO number, the more light your camera is letting into the sensor, the faster your camera will take the shot. The downside being , the higher the ISO number, the more grain you will see in the image you look at on your computer.
Learn how to use a good noise removal software for those times when you have no option other than to use extreme ISO Settings, there are plenty of software options available to help Photographers improve the amount of grain/noise seen in their images.
I recommend Nik software and a Popular stand alone software called Noise Ninja can be download. Many Photographers intentionally us high ISO settings to add grainy effects to their images for artistic purposes. Be Creative and try different approach.
In next lesson I’ll talk about Shutter Speed.