ISO Speed

Okay...I've been so busy during the holidays that I never got back to my posts about taking pictures! Here we go!!! Let's start with ISO. We used to call this "Film Speed". It was that number on the outside of the film box...100, 200, 400, etc. The numbers are still around, but now they are displayed on the back of our digital cameras in the LCD screen. If you haven't discovered how to change your ISO setting, run to find your manual right now and look it up. You will love it! Typically, it will be set on automatic, which works...most of the time. But you will be amazed how much it can help once you know how to control it!
So, what does it do. It tells the camera how sensitive the camera should be to light. 100 is the least sensitive, so it takes more light to create a well exposed photo (translate that as longer shutter speeds or larger aperture). 1600 is one of the highest (on most cameras anyway) and takes less light. So what's the catch? Why don't we always want to use higher ISOs allowing us to shoot with less light. Well, 100 ISO allows sharper detail. If you are taking portraits, there is no motion, you can handle less sensitivity and get super sharp detail. With 1600 ISO, you can shoot in lower light, but you'll have more "noise". Think about the black and white sports shots you used to see that looked really grainy. Those were probably 1600 or 3200 ISO. Generally you want to use the lowest ISO you can get away with.

Now for some visuals. These were all shot on manual settings. 1/60 shutter speed and f-stop of 5.6. Refer to the earlier post if you need a refresher on what that means. The only thing I changed was the ISO setting.

ISO 1600

ISO 800

ISO 400

ISO 200

ISO 100

You can see the dramatic difference between ISO 1600 and ISO 100.

I was shooting a graduation once (my husband's). I was toward the back of a large arena with my zoom lens. I really wanted to get some great pictures of him receiving his diploma. I took a test shot...nothing! It was totally black! I tried lowering the aperature...slowing the shutter. No difference. I grabbed my manual, figured out how to manually set my ISO and cranked it to 1600. I took a test shot. A great exposure! It was a little grainy. But I got pictures of my husband's grandfather handing him his doctoral diploma...and they are pretty good. Now translate that to your daughter's dance recital, a wedding reception, etc. It's a great tool for you to know how to use. Give it a try! Go take some shots experimenting with ISO. Let me know what you learn!

Happy shooting!
Lori