Three Image Models Tried to Change 70% to 50%. One Changed the Wrong Text.

Description and use

Out of eight requests, five outputs passed the text checks and were selected for publication; three contained incorrect edits (e.g., Qwen changed SALE instead of 70%). The experiment demonstrates that providing more context (full line replacement) can improve accuracy but does not guarantee it.

Problem

Ensuring image‑editing models replace only the intended text in a photograph without altering other visual elements.

Outcome

Out of eight requests, five outputs passed the text checks and were selected for publication; three contained incorrect edits (e.g., Qwen changed SALE instead of 70%). The experiment demonstrates that providing more context (full line replacement) can improve accuracy but does not guarantee it.

Workflow

• 1. Prepare source image and prompt: "Replace only the following text in the provided image: 1. "70%" -> "50%" Match each original text's lettering style, size, weight, color, spacing, alignment and perspective. Keep all other text and image content unchanged. Do not add grain, distressing, texture or other visual effects absent from the source image."
• 2. Submit the same image and prompt to Grok, Nano Banana, and Qwen.
• 3. Evaluate each output: check that the target text is replaced, that no other text or background is altered, and that lettering matches the original.
• 4. If the target is ambiguous, modify the prompt to replace the full line (e.g., "UP TO 70% OFF" -> "UP TO 50% OFF").
• 5. Re‑evaluate the new output for correctness and unintended changes.
• 6. Document successes and failures, noting any changes to surrounding imagery or incorrect digit rendering.
• 7. Use the documented review routine (read new text literally, read unchanged text, compare lettering and surroundings, treat more context as another attempt).

Evidence

We asked three image‑editing models to change 70% to 50% on a shop-window sign.

Source

The first Qwen output replaced the large SALE with 50% and left the original 70% on the lower line.

Source

Grok and Nano Banana both changed the lower line to UP TO 50% OFF while keeping the large SALE in place on their initial outputs.

Source

We also tried changing a chalkboard menu price from 2,5 to 2,8. The first Grok output wrote 2,6. A later Nano Banana call wrote the requested 2,8.

Source