A bright rectangle obscures the eyes behind glasses. It is often the reflection of a window or softbox. Simply reducing exposure does not selectively remove it; the face becomes darker too. Identify the source and change its angle relative to the glasses and camera until the eyes become visible again.
Follow the reflection deliberately
Ask the person for a very small head turn and watch the lenses in the viewfinder. A slight change can move the reflection away from the pupil. Check both lenses because their angles differ. A position that works on the left may still leave a distracting bright area on the right.
When moving a lamp, change only height or lateral position at a time. This shows which direction moves the reflection. Check facial shadows simultaneously. Reflection-free glasses are little gain if the eyes then fall into deep shadow or the pose looks unnatural. The person should remain comfortable in the position.
Windows and other bright surfaces
With window light, the source cannot simply be moved. Shift the person and camera in small steps relative to the window instead. A bright wall, monitor or your own pale clothing can also appear as reflections. Remove unnecessary sources or change position before building a complicated lighting setup.
A polarizer is not a universal solution for every pair of glasses. Its effect depends on angles and material, and it absorbs light. Different coatings can also leave coloured reflections. A controlled position change is therefore usually the simpler first attempt. Assess a magnified capture because small reflections are easily missed on the camera display.
Preserve eyes rather than invent them
A small reflection away from the eyes can belong to the natural appearance of glasses. If a reflection completely covers the iris, however, real image information is missing there. Later retouching would have to reconstruct it. For a credible portrait, an additional clean frame at the location is usually better. Check frame edges, eyelashes and focus as well: transparent lenses alone do not make the eye sharp.
