Changing one Photoshop Drop Shadow angle can rotate other layer shadows when those effects use Global Light. The layers can remain completely separate while their enabled effects share a lighting direction. Inspect each effect's Use Global Light setting before looking for merged layers or trying to repaint the photo's real illumination.
Identify shared effect lighting
Adobe's documentation gives Layer > Layer Style > Global Light for the document's global lighting angle. It also shows Use Global Light inside relevant layer effects, including Drop Shadow, Inner Shadow and Bevel & Emboss. This setting concerns those procedural effects; it does not synchronize every layer property or relight the photographed objects.
In an editable photo-card layout, identify two independent card layers and their effect entries. Open each relevant Layer Style dialog and record whether Use Global Light is enabled. Also record the effect's angle and other visible settings. A shared angle is different from shared pixel content, linked movement or an adjustment layer affecting multiple objects.
Compare two independent layer samples
This is a reproducible test plan, not a completed Photoshop experiment. In a working copy, prepare two clearly separated card layers with visible Drop Shadows. Give the layers different names and retain their independent content. Record the starting effect settings and save a reference image of the whole layout.
With both shadow effects using Global Light, change the lighting angle through the documented route and compare both shadows. Inspect the Layers panel as well as the canvas. The expected diagnostic observation is shared direction while the two layer entries remain separate; it is not that the photographs themselves acquire new sunlight.
Then make a second controlled comparison in the copy. Disable Use Global Light for one layer's relevant effect, record its independent angle, and change the global angle again. Compare which shadow responds. Keep opacity, distance and size recorded so an unrelated effect change is not mistaken for proof about shared direction.
Choose global or independent intent deliberately
For a hypothetical album-cover layout, several flat photo cards should look illuminated from a common direction. Keeping their relevant effects on Global Light can support that design. A separate decorative element may intentionally need a different shadow angle. This planning example has not been executed and does not establish a universally correct lighting style.
Choose the setting according to that intent rather than unchecking it everywhere. An independent shadow can become inconsistent with the rest of a layout, while a shared shadow can frustrate a deliberate exception. Document which effects should participate. Do not infer that all angles, sizes or other values have been locked together merely because one setting is shared.
Accept controllable layers and coherent shadows
Require two independently editable layers, the intended shared or independent angle behavior, and a convincing final layout at delivery size. Reopen the saved working copy and verify the settings. Compare the photographic content separately to confirm that an effect adjustment did not become an unintended edit to the image itself.
Imagild can supply a creative photo treatment or artwork through its current visible controls. Photoshop's Global Light is a separate desktop layer-effect workflow. It does not diagnose a real product's double shadow or claim to change the actual lighting captured in a photo. Keep the layered finishing file when future shadow adjustments are part of the handoff.