|Visitors photographing fish|
Florida Aquarium, St. Petersburg, Florida
When you photograph in dim lighting indoors, your camera may fire the flash in Automatic exposure mode. In a situation like this, where I'm facing a large window, light from the flash would reflect off the glass, leaving a large white spot and obscuring the fish in the water.
If you switch the camera to Program (P) mode, the flash does not fire automatically. (You can turn it on if you wish.) But the scene is still quite dark. By increasing the ISO setting to 3200, I made the camera more sensitive to the light coming from the aquarium itself. This enabled me to make a photo of the visitors using their cell phones to record the saltwater fish.
Learn when to adjust the ISO and other camera settings in Getting to Know Your Digital SLR Camera, an online course beginning November 2, 2020, at the Lifelong Learning Center in Missoula, Montana. Click here to register.