The exposure is controlled by the camera's light meter

They are not.The exposure meter won't work with the ais lenses.

They will work fine if you get the exposure right from trial and error, use a light meter, use experience or meter with another lens first though.

If you mean a light meter that is used in a photographic studio, then it measures the light that hits the 'subject' from the studio lighting, the light meter then tells you what you need to set your camera to, for the correct exposure.

You will increase the film exposure compared to what the on board light meter is suggesting. This is known as over exposure, but that is a relative term. "Over exposure" is not necessarily a bad thing.

A light meter is used to measure the amount of ambient and reflected light in photography. This helps to determine the proper exposure for a photograph. A company called Weston marketed the first photographic light meter in 1932.