Nano Banana 2.1 8:1 and 1:8 images: banners and strips on Sume

Yes. On Sume, google/nano-banana-2.1 lists 8:1, 4:1, 1:4 and 1:8 in its aspect-ratio descriptor, and google/nano-banana-pro does not. fal's page for the model also states aspect ratios from 8:1 (panoramic) to 1:8 (vertical strips). The listed rate is $0.08 per image at 1K, which is $0.10 billed (list x 1.25).

Which rows list the extremes

Wide ratios are a catalog question, not a prompt trick: a ratio the row does not list is rejected. This table is built from the repo's capability data.

Request

Send the ratio and a resolution tier. A 4K request at a long ratio is the likeliest to pass the 30-second wait and return 202, so read the status code. The snippet requests a site header strip.

If you need an exact pixel size, generate at the ratio and crop or resize afterwards; the Image API docs describe image_size custom pixels for some models, with Banana converting 1080x1350 into a ratio plus a post step.

import os, requests

r = requests.post(
    "https://api.sume.com/v1/images",
    headers={"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"},
    json={
        "model": "google/nano-banana-2.1",
        "prompt": "wide misty mountain ridge at dawn, empty sky on the left",
        "aspect_ratio": "8:1",
        "resolution": "1K",
    },
    timeout=60,
)
print(r.status_code, r.json())

When to pick it

• Page headers and ticker strips: 8:1 or 4:1.
• Scroll-down infographics: 1:4 or 1:8.
• Standard social ratios: any row; 4:5 is listed by Banana, Seedream and Flux.