After pairing an 8 gigabyte secure digital card with your digital camera, check the front of your camera for a label noting its megapixel rating, usually listed as MP. The number of images you can store on the SD card depends on the type of image and the size of file the camera creates. The more complex the image and the larger the megapixel rating, the fewer pictures you can store on the media card.
According to the SD Association, 3,080 photos recorded with fine compression on a 10 MP camera will fill an 8 GB SD card. To find out the estimated number of photos specific to your camera, slip the SD card into the camera.
Turn the digital camera off.
Slide the memory card door open. Insert the SD card with the notched edge going into the camera first. Close the memory card door.
Turn the camera's power button to "On."
Twist the camera's command dial on the top of the camera to a shooting mode, such as "Auto."
Press the "Display" button -- located on the back of camera near the LCD screen -- to show data on the LCD screen.
Look for a number displayed on the lower-right or upper-right corner of the screen. This number indicates how many photos you can take before the card reaches maximum capacity.
Press the camera's "Playback" mode button on the back of the camera to review how many pictures you've already recorded on the card. Look for a fraction, such as 50/52. This indicates you're viewing the 50th photo taken, and the card contains 52 saved photos.
Add the denominator number from the fraction to the first number you located to estimate the 8 GB SD card's storage capacity.
The number indicating how many photos you have left to take is an estimate. You will fit more photos than that number on the SD card if you shoot simple, monochromatic images such as pictures of blue sky or green grassy fields.
You will fit fewer photos than the counter indicates if you photograph complex, detailed images. Colorful, texture-heavy pictures of a circus ride or pile of multi-colored wrapped birthday gifts contain more data to record, which takes up more space on the SD card.
Never insert or remove an SD card from a powered-on camera. This can scramble and damage image files.