ISO 101 #Photography

It’s been a while since I wrote a photography tutorial post…life has been busy, to say the least! But I’m ready to pick up where we left off. I wrote about aperture and shutter speed in the past, so today we focus on the third aspect of the exposure triangle: ISO, which is just as important as the other two factors, but in a different way.

ISO controls the sensitivity of the sensor, so if you are taking photos in low-light situations (indoors or at night, like you see in my photos above of my son when we were decorating for the holidays), dialing up the ISO would allow you to still take photos without resorting to your in-camera flash, because you made the sensor more sensitive to any and all available light coming in through the lens. At ISO 800 my son was still very underexposed, but if I slowed down the shutter speed, he would look blurred as he ran around, and if I lowered the aperture, it would have been near impossible to get him in focus.

ISO doesn’t really have a creative affect like` shutter speed (which allows you to freeze and imply motion) or aperture (lets you choose how much of the shot is in focus), but changing your ISO is the reason you can get more creative with your shutter speed and aperture. The ISO is the work horse of the camera, it picks up the slack. If you need your photo to be less exposed, you dial your ISO way down so you can keep your desired shutter speed and aperture, and if you need more light, you dial your ISO up without changing the overall vision of the picture.

Isn’t ISO wonderful?

The only problem occurs when using higher ISO’s on a camera that doesn’t handle it well. While fabulous at getting shots that other cameras would require flash to achieve (or not be able to capture at all), it can produce something called “noise” (grain or specks) in your photography, so generally, you keep your ISO as low as the situation will allow.

If you have to choose between a little noise or a blurry, unfocused shot, you are better off with a little noise (blurry, unfocused shots are never a keeper, but as you can see, a noisy shot like the one above is perfectly acceptable). Because I photograph for fun and don’t want to miss a single precious moment with my boys, I don’t mind noise (pun intended).

* A higher ISO allows you to close up your aperture to get more of your picture in focus- great when you are taking scenery shots at night or large group photos indoors.

* A higher ISO allows you to use a higher shutter speed so you can freeze motion, not get blur if you accidentally shake your hand, and capture fast moving toddlers.

When to shoot with a higher ISO:

• When shooting night photography
• When shooting indoor photography and getting the shot at the right moment is more important than getting a perfect shot (like at a surprise party, or when your child is doing something totally awesome for the first time and you can’t tell him to go outside in the daylight and repeat it for a clearer shot
• When you want a picture to look a little grainy (if it’s the creative effect you are going for, sort of a Norman Rockwell like photo)

Quick tips on ISO:

Outdoors in bright sunlight – 100
Outdoors in shade or indoors in bright light – 200-400
Indoors near a well-lit window or good lighting 400-800
Indoors in low light or at night – 1600+

Happy shooting!