Build a repeatable setup
Use a neutral surface near soft window light or two diffused lights. Mount the phone or mark its position so every card is photographed at the same distance and angle.
Control glare
Tilt the light source rather than the card whenever possible. Refractors, chrome finishes, slabs, and penny sleeves may require small angle changes to reveal the surface without reflecting the room.
Show condition honestly
Capture the full front and back with corners visible. Add detail images for creases, scratches, print lines, edge wear, surface flaws, or slab damage that could affect a buyer's decision.
Name and store images consistently
Attach images directly to the card record so they do not become an unlabeled camera-roll archive. Keep the original resolution and let the listing workflow create appropriately sized versions.