Shopify Magic image editor: 1 MP default vs Sume tiers

Shopify's media generation in the file editor produces 1 megapixel images by default, based on your image's aspect ratio. Larger images are scaled down and smaller ones scaled up. The Sume image API lets you pick the size per request instead, with a resolution tier of 512, 1K, 2K or 4K, subject to what the model supports.

Shopify's behavior is from its Help Center page; Sume's from the image generation docs, both read 2026-10-01.

What does Shopify's editor do to image size?

Shopify advises using images close to 1 megapixel in dimension. Modified images are saved in the original format, and Shopify says transparent backgrounds need a new PNG file. It also states an invisible watermark is applied to all generated images; that is Shopify's behavior, and Sume's docs cited here make no equivalent claim.

How do I choose a size on Sume?

Set resolution to a normalized tier and aspect_ratio to a ratio from the documented list, such as 4:5. A model only accepts the values its catalog descriptors list, so read supported_parameters before pinning a tier or ratio. size is shorthand for a tier and must not carry custom pixels; use image_size or aspect_ratio for that.

{
  "model": "google/nano-banana-pro",
  "prompt": "a product photo on a kitchen counter, warm light",
  "resolution": "2K",
  "aspect_ratio": "4:5"
}

What should I know before asking for 4K?

The docs say slow configurations, including 4K, high quality and large n, are the most likely to degrade to a 202 job envelope. Check the status code, then poll GET /v1/jobs/{id}/status and read the result. For edits, prefer aspect_ratio: "auto" to match the reference. See also gpt-image-2.5 resolution.