Seedream 4.0 vs Nanobanana - Canton Tower Background Swap + Hair Recolor

Two edits: portrait cutout + background replacement + lighting match; and hair recolor. We evaluate hair/transparent edges, depth/perspective consistency, hue/lightness match, and spill control on skin/garments.

Seedream 4.0 better preserves flyaway hair and semi-transparent areas (e.g., veil, loose hair) with fewer jaggies; Nanobanana can show hard-cut edges on complex backgrounds.

With Canton Tower as the new background, Seedream 4.0 rebalances subject color temperature and key/fill ratio with better shadow alignment; Nanobanana may produce subject color casts or edge glow.

Seedream 4.0 keeps a stable light-brown hue and preserves highlight distribution; Nanobanana can warm the whole image and shows uneven dye at roots/ends.

Seedream 4.0 better avoids tinting skin, teeth, and white garments; Nanobanana more often leaks color in high-contrast zones. Metallic jewelry reflections are better preserved by Seedream 4.0.

Across retries, Seedream 4.0 is more repeatable; Nanobanana requires tighter prompts and more sampling/curation.

Prefer Seedream 4.0 for ecommerce scene swaps, portrait retouching, and brand compositing. For stylized art composites, Nanobanana plus manual masking/second-pass editing can work well.

Be explicit: cutout semantics (fine hair segmentation, preserve transparency), background params (Canton Tower at dusk, matched perspective), lighting (match key direction, soft rim), and color constraints (hair hue: light brown; preserve skin tone).