All images for a spherical virtual reality (VR) panorama must be shot using the same exposure, so shutter speed and aperture must be set manually. Autoexposure mode cannot be used because the exposure would be changed as the camera was rotated and the angle of the light changed. Before beginning the process of taking the shots, check the exposure in all directions and observe how the light changes. Then try to find the best compromise to suit all directions. RAW mode allows some recovery of detail where necessary. In high-contrast situations, use exposure bracketing of one or two stops and then combine the images to incorporate all the necessary detail.
It is obviously somewhat easier to work in a location where there is no direct sunlight. Choose a period of time where the Sun is obscured by cloud cover or position the camer and tripod in a shadow cast by a large object such as a tree or building. Where no shade exists, it may prove very difficult to complete a panorama because at least one image must incorporate the disc of the Sun with obvious implications for exposure.
High Dynamic Range (HDR) photography overcomes dynamic range limitations by combining several images exposed using bracket settings. The resulting image should incorporate all the detail in dark areas and highlights. Another approach, made possible by some image stitching software, is known as "exposure fusion". This process is broadly similar to the HDR technique but creates a tone-mapped panorama directly from the original exposure- bracketed images.
Note that when bracketing images, only the shutter speed should be varied. Changing aperture also changes depth of field, and varying the ISO setting changes the amount of noise recorded in the images.