People love to photograph and use their digital cameras with a light meter to check exposure and make sure their images are bright and sharp.
It’s easy to lose sight of the basics of light meter reading and calibration, and sometimes you have to put your camera in manual mode to get your hands dirty.
If you’re a photographer with a camera that has an autofocus sensor, you can learn to use the light meter on the Canon EOS 5D Mark III camera to read and calibrate the sensor.
If that camera is a Canon E1D Mark II, then you can skip the manual calibration part and focus on the autofocusing function.
Here’s how to get accurate readings of the ISO, shutter speed, and light meter.
You can get the ISO reading of the camera using the camera’s camera software, and you can use the shutter speed reading of a digital camera’s shutter speed sensor to get an accurate reading of ISO, and ISO sensitivity.
The shutter speed can also be read by using the built-in camera software.
You’ll need the Canon Lens Performance Analyzer (LPA) app on your iPhone or Android device to calibrate ISO sensitivity, ISO reading, and exposure.
We also recommend the Canon Light Meter Calibration app, which will help you set up the calibration, but it won’t let you use your own ISO setting.
Here are the steps to getting the best ISO reading with your Canon E3, E4, E5, E6, E7, E8, E10, and E11 cameras.
Find the ISO value of your camera.
Open the Canon Camera app on the phone or tablet and tap the menu button to find the ISO menu.
The menu will pop up to display the ISO readout for the camera.
Tap on the ISO range and choose the camera with the lowest ISO reading.
Choose your exposure.
Tap the exposure menu to find out the shutter and ISO setting of your exposure in seconds.
The ISO setting should be a decimal number that is in the range from 0 to 100, where 100 is the highest ISO reading available.
Tap any of the buttons in the exposure bar to change the exposure, and tap a button to apply the new exposure.
The camera will display the time elapsed since the shutter opened and the exposure readout.
Tap this bar to adjust the exposure setting and apply the exposure.
You may need to turn on the white balance, if you’re using a tripod, and then tap the exposure slider to adjust exposure, as well as turn on a timer.
You will see a time stamp in the lower left of the screen to display when you’ve completed the calibration.
Press the shutter button to open the camera, and press the ISO button to start the exposure calibration.
Once you’ve set the camera to your desired ISO, you will see the time displayed.
Tap and hold the ISO slider to select the exposure in meters per second.
You should see the meter fill up as the ISO is calibrated.
Once the meter fills up, the exposure will display as a percentage of the original ISO value.
Tap to set the exposure again, and repeat the calibration process.
You might need to take a photo in the dark or a bit more light to get a good reading.
When the meter is at 100 percent, tap the ISO to set a new exposure for the exposure that you’ve chosen.
The exposure should be as bright as possible.
Tap again to set another exposure.
Press and hold ISO to select an exposure for later use.
If your camera’s autofocal sensor has a built-up sensor, tap ISO to calibrates the sensor and you will get the full ISO reading when you calibrate your ISO.
Repeat the calibration steps as necessary until you get the reading you want.
For more on light meter calibration, check out our Light Meter Guide.
If all goes well, the image displayed will be the same ISO as the original, or if the exposure is too dark, you’ll need to adjust your exposure accordingly.
This can be done with the camera software or with your iPhone camera app.
If the exposure was too bright, tap on the Exposure slider to set it back to the desired value.
If there’s a lot of light coming through, you might want to check your exposure settings with the Light Meter app, as the meter will fill up with light when the exposure isn’t as bright.
The Light Meter also has a “dark meter” that you can set to read the ISO that your camera is set to, and adjust your ISO accordingly.
The image displayed on the screen will be a combination of your ISO, ISO sensitivity and the ISO sensitivity in meters, so you can see if you have the right exposure for your lighting conditions.
If no light is coming through the sensor, then