50D How to set white balance correctly with grey card?

50D Method of setting white balance with grey card:

Grey card can be divided into white surface and grey surface. Custom white balance is used to define true white in any environment. In fact, the white balance can be accurately restored by using the white surface and gray surface of the gray card.

Generally, it is customary to define the white balance with the gray surface of the gray card, because it is convenient for accurate metering after defining the white balance.

To customize the white balance of the gray card:

1. Switch the lens of 50 1.8 from AF autofocus to MF manual focus.

2. Adjust the focal length of the lens to infinity.

3. Set the Canon 50D camera to AV mode (aperture first), the exposure value depends on the normal exposure index measured on the gray card, and the metering mode is set to normal shooting scene.

4. At this time, the camera white balance setting can be any option, so I choose to set it as AWB option here (Note: Because our ultimate goal is to customize the white balance, the custom benchmark is actually a white balance setting that automatically corrects errors, so the white balance at this time can be set as any option).

5. Shoot at the gray card, make the gray card fill the whole lens, and ensure that the gray card and the subject are in the same lighting environment.

6. Check the shot gray card picture to ensure that the gray card picture is clean, for example, there is no projection of other objects.

7. Find and open the camera's "Custom White Balance" option-"Customize the white balance with the white balance data of this picture" (find the gray card picture that was just taken under the living light)-click "OK".

8. Return to the camera's white balance setting option again, and select the user-defined white balance option. Finally, complete the custom white balance setting of the gray card.