Part 1: Advanced learning
fujifilm digital cameras
When to Change ISO
Mood lighting, anyone?
Being able to change ISO on the fly is one of the most significant advantages that digital cameras have over their film counterparts.
This brings us to an important question: why should you change the ISO rather than letting the camera decide for you?
More importantly: when should you change the ISO setting on your camera?
The answer will significantly increase the quality of the photos you take.
When the Lights are Low
I’m not going to define ISO here. I’ve already done that on a different page where I talk about ISO and image noise.
I will provide a short definition: ISO is an indication of how sensitive your camera’s sensor is to light. The higher the ISO number, the greater the sensitivity.
Put another way: increasing the ISO of your digital camera helps it to “see” in the dark.
I just tipped you off to the answer to the question I posed above…
You want to manually increase the ISO setting on your camera when you are taking photos in dim light conditions AND you don’t want to use the flash.
I’ll get into more details about this in just a moment. Before I do, take a quick look at this chart to see the relationship between certain lighting conditions and the ISO setting:
Lighting ISO
Bright sunshine 100
Mild shade or overcast 200
Deep shade 400
Indoors on a sunny day 800
Indoors at night 1600
The important thing to note: as the light gets dimmer, the ISO must increase accordingly.
It’s All About Shutter Speed
Let’s delve a bit deeper into the specifics of when you should change the ISO setting.
First, a question for you: don’t you just hate it when a prime photographic opportunity comes up and your photo turns out a blurry mess?
I certainly do. It drove me crazy when I first started using digital cameras that half my photos were blurry. So many shots that could have turned out great were immediately deleted.
That’s because I didn’t know how to properly leverage my ISO setting to get a fast shutter speed.
A slow shutter speed is what causes a blurry photo.
Here’s a more detailed description: a shutter speed that is not fast enough to freeze the motion of your subject will result in a blurry photo.
This means that you can take a perfectly clear portrait using a shutter speed of 1/60th of a second (because your subject is still) but a photo of a running horse at 1/60th of a second will be a blurry mess.
Here’s a quick table to help you determine the approximate shutter speed required for different subjects:
Subject Shutter Speed*
Landscape 60
Portrait 125
Children 250
Animals 500
Sports 1000
Race Cars 4000
* Shutter speeds are measured in fractions of seconds, so 60 is really 1/60th of a second.
One factor that contributes to blurry photos is how fast your subject is moving.
The Focal Length Factor…
Fuji Finepix S1000fd 10MP Digital Camera with 12x