That IS the use-case for Nano Banana (as opposed to pure generative like Imagen4).

In my benchmarks, Nano-Banana scores a 7 out of 12. Seedream4 managed to outpace it, but Seedream can also introduce slight tone mapping variations. NB is the gold standard for highly localized edits.

Comparisons of Seedream4, NanoBanana, gpt-image-1, etc.

https://genai-showdown.specr.net/image-editing

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simonw 8 hours ago | parent [-]

I tried your "Remove all the brown pieces of candy from the glass bowl." prompt against Nano Banana Pro and it converted them to green, which I think is a pass by your criteria. Original Nano Banana had failed that test because it changed the composition of the M&Ms.

https://static.simonwillison.net/static/2025/brown-mms-remov...

	▲	vunderba 8 hours ago \| parent [-]
		Thanks Simon - I'm in the middle of re-running all my prompts through NB Pro at the moment. Nice to know it's already edged out the original. It also passed the SHRDLU test (swapping colored blocks) without cheating and just changing the colors. I'll have an update to the site shortly! EDIT: Finished the comparisons. NB Pro scored a few more points than NB which was already super impressive. https://genai-showdown.specr.net/image-editing?models=nb,nbp