OpenAI’s new image model, ChatGPT Image 2.5, has improved an over-sharpening issue flagged in its previous version, but a comparison with Google-side Nano Banana 2 was too close to call. In six evaluation categories, the two models each won three, producing a near draw. ChatGPT Image 2.5 performed better in spatial composition, mood and illustrations, while Nano Banana 2 more reliably handled verifiable details such as text and dates.

Complaints are spreading among users that Google’s AI image-generation model Nano Banana 2 is producing lower-quality images than before, with posts on Reddit dating back to May. TechRadar reported users said recent outputs look bland and do not improve even with detailed prompts. The outlet ran three scene tests and said ChatGPT’s results generally looked more natural than Gemini’s, though Gemini generated images faster.