How does the exit pupil diameter affect viewing comfort?Updated a day ago

Ideally, the exit pupil diameter of the binoculars should match the entrance pupil diameter of the observer's eye. Only then can the full light performance of the binoculars be utilized by the observer. The pupil size of the human eye is individual. Although the eye's ability to dilate decreases with age, it is not advisable to rely on generalized numbers. Not all 20-year-olds, have a maximum pupil opening of 7mm, nor do all 60-year-olds have a pupil width of 3mm. One thing is certain however: binoculars with an exit pupil larger than the observer's pupil offer advantages when it comes to observation comfort. The edges of the aperture are less noticeable, and hand tremors result in a less apparent shaking or wobbling of the visual field. While the user may not be able to take full advantage of the binoculars' performance in darker situations, they are compensated with a steadier image.