Today we’re talking about exposure — overexposure (and underexposure) As relates to cameras. I’ll be simplifying it for kids, as has been the norm with my Photography ABCs series. Make sure to read through to the end, because I’m sharing three activity ideas to help kids learn about overexposure and underexposure. So, let’s get started. What’s exposure? Or, more specifically, what are overexposure and underexposure?
Underexposed, as defined by Dictionary.com:
1. inadequate exposure, as of photographic film.
2. a photographic negative or print that is imperfect because of insufficient exposure.
Dictionary.com defines overexposure as follows:
1. excessive exposure, especially of photographic film or a sensitized plate to light rays.
2. the condition of having been seen, heard, or advertised so frequently or for so long that freshness or appeal is diminished.
You’d probably recognize overexposed images if you saw them. They tend to be overly bright, with loss of detail. Want a simplified definition of overexposure? Too much light. You know how you can’t see anything when you first go outside into the bright sunlight? You’re blinded. Blinded because your eyes are adjusted to the dim indoor light, and when the brighter light from the sun reaches your eyes they are overwhelmed — it takes a few moments for them to adjust and compensate. Remember the lesson on aperture, and the one where we made a camera obscura? These are related to the concept of exposure. And overexposure.
Light enters the camera.
The right amount of light, and you can create a stunning image.
Too much light, and you end up with an overexposed image — if taken to the extreme, it would be a white rectangle. Too little light, and you get an underexposed image — taken to the extreme, it would be an unexposed black rectangle. But we’ll get to that later.
To simplify this concept — If you take a picture of your yard during nighttime, it will likely be very dim and dark. Possibly underexposed, if you use your camera’s auto settings (and no flash). The camera tells the flash to fire so that it will be the correct exposure, so that it will have enough light in the picture. If you take a picture of your yard during the daytime, the camera usually tells the flash not to fire — because then it would have more light than it needs, and the image could be overexposed.
Cameras aren’t all that smart, though. If you take a picture of a person with the sunset behind them, it might underexpose the scene (and render the person a silhouette) in order to properly expose for the sunset. If it exposes the image for the person, the sunset portion of the image would be overexposed. That’s where the flash comes in (yet again) — it adds more light to the person, so they will not be underexposed. Of course, the flash has no effect on the sunset, because that is WAY too far away.
Over/Under Exposure Camera Activity
For today’s activity, you’re going to need a camera.
Turn off the on-camera flash, and try taking pictures of different things around the house. Notice how when you take a picture of your sofa next to the window, that the camera tries to expose for one of two things — the sofa (dimmer inside light) or the yard (brighter outside light). Take a couple pictures, and see how the camera either overexposes the outside or underexposes the inside, depending on the image.
Now, turn on the flash and see if it makes a difference.
This activity is really simplified. Have your kids draw a picture of a tree at night, or their bedroom with the lights off.
Tell them to use their imagination and draw something that is not shown clearly because there is not enough light (underexposed). Suggest they use dark colors if they need prompting. A candle in a bedroom, for example, might be a paper colored completely black, with just a little orange glow. You can’t see the bed, or more than a shadow of it, but you know it’s there.
On the flip side, have them draw something that is so bright it can’t be seen clearly (overexposed). Ideas you could prompt them with include a car with its headlights on, a polar bear in the snow (e.g. three dots, a nose and two eyes).
It will be interesting to see how your kids interpret this, and will vary depending on their ages.
You don’t need anything except your eyes for this activity. Take your kids from a brightly lit room into a dark room. Tell them to pay attention to how their eyes adapt, how nothingness becomes dark shadows, which in turn becomes identifiable objects.
Then, return to a bright area. The opposite happens.
If you wanted to, I guess you could let them shine a flashlight into their eyes for this portion too. Not condoning that, but it definitely would illustrate the concept of overexposure. Way too much light to see what anything is.
Have more ideas?
I’d love to hear your ideas, if you have any more thoughts on activities for overexposure and underexposure, in the comments below. Or, if you try these activities I’ve mentioned, I definitely want to know how things go for you!
Make sure to check back next week for the next post, where I’ll share an activity for the letter P. You might also enjoy revisiting last week’s activity where we learned about negative.
Join Betsy as she works through the alphabet in this educational series for kids… The ABCs of Photography! We’ll cover topics from A to Z, with activity ideas for both younger and older kids
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