On a bright, but hazy day with soft shadows, which aperture should be used to convert film speed to shutter speed?

The choice of f/8 for shooting on a bright but hazy day with soft shadows is beneficial for several reasons. At f/8, the aperture is small enough to provide a decent depth of field, which ensures that more of the scene is in focus. This is especially important in landscape photography or when capturing environmental portraits, where you may want both the subject and the background to be sharp.

Additionally, f/8 is a versatile aperture for reducing the potential for overexposure in bright conditions while still allowing adequate light to enter the camera. The hazy conditions diffuse the light, so f/8 allows you to capture the soft qualities of the light without losing detail.

Using a smaller aperture such as f/11 may further reduce light and increase depth of field, but this could also lead to diminished sharpness due to diffraction, especially if the light is already soft. On the other hand, wider apertures like f/2.8 or f/5.6 would let in too much light, potentially resulting in overexposure without the ability to effectively control shutter speed in bright conditions.

Overall, f/8 strikes a balance between depth of field and exposure control, making it the most suitable choice for the described lighting conditions.