Which settings are needed in this situation in order to have equivalent exposure?

Question

Two Wedding Videographers will cover a wedding ceremony. Both use a Canon Eos 80D DSLR camera with different lenses.
The first videographer used a Canon EF 50mm F / 1.8 lens with aperture settings (ISO: 400, F: 2.8, and SS 1/250)
The second videographer used a Canon EF 18 - 55 kit lens.
How is a second videographer change the settings so that they both get the same Normal lighting with the first Videographer if the ISO remains the same at 400 ?

WayneF · Answer

Equivalent exposures are:
ISO 400 f/2.8 1/250 second
ISO 400 f/4 1/125
ISO 400 f/5.6 1/60
ISO 400 f/8  1/30
ISO 200 f/4 1/60
ISO 200 f/5.6 1/30
Stopping down one stop of aperture is compensated by one stop slower shutter speed,
OR by one stop smaller ISO.

Michael C · Answer

The second photographer is using an 18-55mm kit lens. At 50mm all of Canon's 18-55mm kit lenses have a maximum aperture of f/5.6.
If one is constrained by using ISO 400 and 50mm in order to match the other camera, then the only variable left is exposure duration, otherwise known colloquially as "shutter speed".
Since f/5.6 is two stops slower than f/2.8 used by the other photographer, the exposure time must be two stops longer.
Two stops longer than 1/250 is 1/60.
So the second photographer must use 1/60 with ISO 400 and f/5.6 to get the same exposure values as the first photographer using 1/250 with ISO 400 and f/2.8.
This presents another issue, however. Assuming both cameras are shooting video at the same frame rate, the footage at 1/250 will look "choppy" compared to the footage shot at 1/60.

Which settings are needed in this situation in order to have equivalent exposure?

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