I've done some digging and I think you have the correct cause of the issue.
http://socialmarketingwriting.com/4-...rest-friendly/
Apparently pintrest wants a 200 pixel minimum and the product image in it's non-enlargerd form is only 120 X 120. The imaged show in the pin it window meet that size criteria.
The product image in it's actual size is 500 x 500. Is there a way to make the image large enough in the smaller form?
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