# Testing product hero images stored in Sanity, does the image live in Croct or Sanity?

Asked by Valeria Duarte on 2024-06-12. Tags: sanity, ab-testing, assets, ecommerce.

i want to A/B test two product hero images against each other. What I cannot
figure out from the docs is where the variant image actually lives. Is the
second image URL stored in the Sanity document, in the Croct variant content,
or in both places? And later, when a marketer wants to swap out the losing
image, what exactly do they edit and where?

## 1 answer

### Answer from rui_p (2024-06-13)

Only the default lives in Sanity. Think of it as two layers:

- The Sanity document holds the canonical hero image. That is what renders
  for everyone outside the test, and it is the fallback when no experience
  applies or a fetch fails.
- The challenger image is variant content inside the experiment. Variant
  content follows the slot's component schema, so if your hero component has
  an image field, each variant has that same field, and you paste the
  challenger's URL there.

You do not duplicate the control into Croct; the experiment layer only holds
what differs.

On the workflow question: variant content is edited in the experience
editor, no code change involved, so a marketer can swap the losing image or
adjust the test themselves. An experiment holds 2 to 5 variants with a
primary goal and a traffic allocation percentage, so a third image later is
just another variant. If the challenger wins and you want it to become
permanent, either roll the winner out from the experiment or update the
Sanity document so the new image becomes the canonical default.