Nano Banana generate tool changes size of image when generating

[Zebbler2]

It's a consistent thing I am seeing when generating things like "new hair color" or altering anything about the image I am working with - the new generation is great, but is almost always different size from the original image, either stretched a little bit, or squished, or larger, or shifted in space, but never exactly perfectly blended with the original image - so it takes a bit of effort to blend the new generation back into the original image.
Seems like a bug vs. a feature to me 🙂

27.0.0 release
Mac OSX Sequoia 15.6.1

[Rafael _ Oz]

i'm having an issue using the "nano banana" model with Generate Fill in Photoshop Beta.

When I generate with a selection that covers the entire image, it works fine and uses the reference photo.

But when I generate using only part of the image (for example, a small selection), the returned result is smaller than the selected area, although the content matches the reference photo. It creates a new layer with the result at a much smaller size and lower resolution. I understand the resolution may be lower than a high‑resolution source, but unlike Firefly it does not produce the result at the exact size of the selection, and I have to manually scale it up using Transform.

[Pete.Green]

Hi @Rafael _ Oz ,

Can you provide a screenshot of what you're seeing?

It'd be great to know how big the image is, what your selection looks like, and what the results are if possible.

Regards,

Pete

[DGoldwas]

When using the Gemini 2.5 (Nano Banana) model for Generative Fill, the resulting image is stretched (horizontally) a little bit.  It's not pixel-accurate.  Using the Flux Kontext Pro model results in pixel-accurate generations.

If you start to stack multiple generations of Gemini 2.5, the final image can be significantly distorted from your original source.

Version: 27.0

Platform + OS: Windows 11

Steps to Reproduce the Problem:

1. Open any image.
2. Select All

3. Generative Fill with Gemini 2.5

4. Toggle the result on and off, you'll notice pixel stretching.

Example:

Original Image:

Generative Fill prompt: "change the weather to be a beautiful sunny day with no clouds"

Result with Flux Kontext: Pixel accurate

Result with Gemini 2.5: stretches a little horizontally

If you stack multiple generations (to keep making changes) it keeps stretching the image each time, to the point where after a few 'iterations' your image is no longer matching the original.

Result with Gemini 2.5 after multiple iterations:

 

Note the shift when viewing the origina layer compared to the generated ones

This stretching does not happy with Flux Kontext Pro, so it's something related to Gemini 2.5.

thanks!
Dan

 

[kind_thinker6068]

I have the opposite problem; after generating, my image gets enlarged.

[CShubert]

Hi @Zebbler2 could you share some screenshots of before and after showing this we can send to the team?

Thanks,

Cory - Photoshop Product Manager