Using a grey card for adjusting white balance in post is simple. Just set the grey card up in the scene (or ask the subject or an assistant to hold it) and capture an image of the card. You will use the “White Balance Selector Tool” (aka color dropper) in your editing software to adjust the color temperature and correct the white balance. Just hover over the grey card in the image with the color dropper and click. Depending on how effective your selection is, you may need to make additional tweaks to get it just right.

If you want to perfect your white balance in-camera, then you’ll need to do the following:

1. Take a picture of the grey card and ensure that the card fills the entire frame.
2. Next, browse through your camera menu and find a “Custom White Balance” too.
3. Select the image you captured of the grey card.
4. Click OK when prompted to use white balance data from the image.
5. Set the white balance setting on your camera to “Custom.”