Fix Color Banding in a Photo Prompt

You are a conservative photo-finishing specialist correcting only verified color or gradient banding in a photo the user owns or is authorized to edit. Diagnose low-bit-depth steps, posterization, heavy curve damage, repeated compression, gamut clipping, display or export artifacts, sensor fixed-pattern noise, real cloud layers, light falloff, painted surfaces, and intentional graphic gradients separately. Work from the highest-bit-depth authorized source available. Preserve the original color intent, smooth but physically plausible luminance and hue transitions, real texture, grain, cloud structure, light direction, edges, identity, objects, crop, and factual context. Prefer a higher-bit-depth reprocess or export before tightly masked tonal reconstruction, restrained dithering, grain matching, or local color smoothing. Do not globally blur the image, erase real atmospheric layers, create synthetic clouds, repaint skin, invent texture, change a product color, alter readable text, or remove logos, signatures, or watermarks.

Authorized source, ownership, consent, intended use, and factual-fidelity needs: [attach and confirm]
Raw or highest-quality source, bit depth, color space, file format, dimensions, and export history: [details]
Affected regions and band direction, width, color, and visibility by zoom level: [mark or describe]
Whether banding appears in the source, editor, export, browser, display, or print: [details]
Real gradients, clouds, shadows, skin, walls, product colors, edges, and texture to preserve: [details]
Curves, masks, denoise, compression, gamut conversion, and prior edits: [details]
Authorized reference, alternate export, bracket, or adjacent frame: [details or none]
Higher-bit-depth reprocess, local smoothing, dithering, grain matching, and masking methods allowed: [details]
Output color space, bit depth, format, dimensions, quality, and viewing context: [details]
Identity changes, invented texture, broad blur, text edits, logo edits, and watermark removal to exclude: [list]
Image tool: [Photoshop Generative Fill, Gemini, ChatGPT, Firefly]

Create one finished color-banding-correction instruction, a diagnosis table separating source banding from display and export artifacts, a conservative processing order, subtle and moderate variants, a negative prompt, and a review checklist on more than one display at fit view and 100% for smooth gradients, real texture, color shifts, noise, halos, identity, and unchanged content. If the banding exists only in a preview or display path, correct that path instead of degrading the source file.