When you select a different photo, the software quickly fades out the previous photo and fades in the selected one. This makes it more difficult to notice subtle light and/or positional changes on the subject. A feature to disable this so that the previous photo is instantly replaced by the newly selected one would be very useful.
You can enable/disable this behaviour by changing the display settings.
The settings is named "Fade Between Image Loading", and you access it by clicking the settings icon at the top of the display window.
I've attached a screenshot to demonstrate where to find this option.
Outstanding. Thank you so much for this response!