Determining exposure using a live histogram display.

An old barn in Central Alberta surrounded by snow.

Some cameras, most notably non-DSLR cameras, may offer an interesting way to figure out exposure.  You can do this on aperture or shutter priority, but it is best done using manual exposure mode.

This may send a spine-tingling sensation up your backbone, but using manual exposure mode is really not all that hard.  I will give you step-by-step instructions below.  The tricky part, which really isn't, is reading the histogram.  Before you can read it though, you have to enable that function in your camera.

The live histogram display is enabled in a variety of different ways.  If you look up your camera's manual, or better yet do it on-line, you should find if your camera has the feature and how to access it.  Generally though, it is done one of two ways.  If you have a display button, try pressing that and looking at the EVF (electronic viewfinder) or rear display.  You should see changes in the way the camera's live image is displayed.  One of those options may include a live histogram display.  The other way involves digging through menus looking for the feature.  Once found, just enable it.

You should get a histogram popping up at the (usually) right corner of your display.  What is unusual about it is that it is live, meaning that as you pan about the room the display will bounce around like an equalizer's graph showing how a song's acoustics change.  The key here is to pay attention to its shape and, when it is right, proceed taking your picture.  Follow the steps below.

1)  Turn on your camera and set the mode dial to manual exposure mode.
2)  Make sure your white balance and ISO settings are where you want them
3)  Change your aperture to whatever value you want, depending on what kind of shot you are doing.  On cameras with only one command dial, it usually means pressing the exposure compensation button (+/-) down AND rotating the command dial at the same time.
4)  Now it is time to change the shutter speed.  The lone command dial by itself will alter this, if there are two command dial it is often the rearmost one.
5)  Look at the histogram display.  If the chart is pushed off to the left it means the photo is underexposed and rotate the command dial so the shutter speed decreases.  If the chart is pushed off to the right it means the image is overexposed and rotate the dial in the other direction.
6)  When you get close you should see the histogram start to even out so that there are no flat areas on either side and no towering areas pushed off like before.  Play with it until you are happy with the image.
7)  To be sure, take a picture and push play on your camera.  Does it look good?  If it is and the light doesn't change, you can keep shooting at those settings.  I find that once I have the values all dialed in I can keep shooting until something significant changes.

Have fun, and keep on shooting!