Dark bands across an indoor photograph can come from flickering illumination interacting with the camera's exposure or sensor readout. If the bands are present in the original capture, changing JPEG quality will not remove their cause. Test the camera and lighting while the scene is available; post-processing is a limited fallback, especially when bands cross a face or product label.
Confirm where the bands enter the workflow
Open the original camera file outside the social app where you first noticed the problem. Compare another photograph made moments later. Broad horizontal or vertical brightness stripes that shift between captures under the same lights suggest a capture problem. Bands that appear only in a resized gradient export need a different investigation.
Also distinguish clothing moiré: it follows a fine repeating fabric pattern rather than crossing unrelated parts of the scene. Record the shutter mode, shutter speed and lights in use if that information is available. Avoid inventing the exact flicker frequency from an ordinary photograph.
Test one capture variable at a time
- Make a reference exposure without changing the composition.
- Try the camera's supported anti-flicker controls according to its manual.
- Compare supported shutter modes or a nearby shutter speed while maintaining suitable exposure.
- If practical, use a different steady light source and repeat the photograph.
Canon documents a high-frequency anti-flicker workflow that adjusts suitable shutter speeds and recommends actual test pictures. Availability differs by model. Mechanical shutter is not a universal cure, and a single familiar mains-frequency setting does not describe every dimmed LED or mixed-light arrangement.
Review saved pictures rather than relying only on the live preview. A slower shutter may reduce bands but introduce subject movement, so inspect the eyes, fingers and garment edges in the new test. A clean background with a blurred subject is not a successful replacement capture.
A hypothetical shop portrait
Suppose a shop owner photographs a colleague under ceiling LEDs. Dark stripes cross both the white wall and the colleague's cheek. A second test with a supported anti-flicker option has fewer stripes, but the person's hand moves. The owner repeats the pose and checks the saved full-resolution file before selecting the reference.
This is a proposed comparison, not a claim about a tested camera. It adds two acceptance conditions: even illumination and intact subject detail. Upload only the accepted source to an Imagild portrait or photo workflow.
If you cannot photograph the scene again
Work on a duplicate. A modest local tonal adjustment may make a faint band less distracting, but severe stripes can contain different color and exposure information. Do not use a full-face generation as proof that the original expression or skin texture has been restored. For a product listing, reshooting is preferable when bands interfere with an important color or label.
When is the image ready?
Check smooth areas, skin and text at the final publication size as well as at 100 percent. Reject repairs with alternating color patches or abrupt local contrast. Keep the original and note any substantial reconstruction. The goal is a dependable photo source, not simply hiding the symptom in a busy artistic effect.