How do I get the best quality?

Start from a sharp, well-lit base image. Describe materials, light and atmosphere precisely — or let the AI write it from your photo with Auto-prompt or the Image scanner — and use typed references for materials and furniture.

For the final shot, NanoBanana PRO; from Basic you can render at 2K, and from Standard at 4K. Then take the render to a photo with Enhance render and raise its resolution with the Image Upscaler.